diff --git a/packages/react-native-codegen/src/CodegenSchema.d.ts b/packages/react-native-codegen/src/CodegenSchema.d.ts
index 2d28bbfe7e271c..3c1ba4b9f4bb1d 100644
--- a/packages/react-native-codegen/src/CodegenSchema.d.ts
+++ b/packages/react-native-codegen/src/CodegenSchema.d.ts
@@ -26,6 +26,10 @@ export interface FloatTypeAnnotation {
   readonly type: 'FloatTypeAnnotation';
 }
 
+export interface NumberTypeAnnotation {
+  readonly type: 'NumberTypeAnnotation';
+}
+
 export interface BooleanTypeAnnotation {
   readonly type: 'BooleanTypeAnnotation';
 }
@@ -42,6 +46,21 @@ export interface VoidTypeAnnotation {
   readonly type: 'VoidTypeAnnotation';
 }
 
+export interface NumberLiteralTypeAnnotation {
+  readonly type: 'NumberLiteralTypeAnnotation';
+  readonly value: number;
+}
+
+export interface StringLiteralTypeAnnotation {
+  readonly type: 'StringLiteralTypeAnnotation';
+  readonly value: string;
+}
+
+export interface BooleanLiteralTypeAnnotation {
+  readonly type: 'BooleanLiteralTypeAnnotation';
+  readonly value: boolean;
+}
+
 export interface ObjectTypeAnnotation<T> {
   readonly type: 'ObjectTypeAnnotation';
   readonly properties: readonly NamedShape<T>[];
@@ -49,6 +68,18 @@ export interface ObjectTypeAnnotation<T> {
   readonly baseTypes?: readonly string[] | undefined;
 }
 
+export interface UnionTypeAnnotation<T> {
+  readonly type: 'UnionTypeAnnotation';
+  readonly types: readonly T[];
+}
+
+// TODO(T72031674): TupleTypeAnnotation is added for parity with UnionTypeAnnotation
+// to support future implementation. Currently limited to String and Number literals.
+export interface TupleTypeAnnotation {
+  readonly type: 'TupleTypeAnnotation';
+  readonly types: StringLiteralTypeAnnotation | NumberLiteralTypeAnnotation;
+}
+
 export interface MixedTypeAnnotation {
   readonly type: 'MixedTypeAnnotation';
 }
@@ -304,10 +335,14 @@ export interface NativeModuleStringLiteralTypeAnnotation {
   readonly value: string;
 }
 
-export interface StringLiteralUnionTypeAnnotation {
-  readonly type: 'StringLiteralUnionTypeAnnotation';
-  readonly types: NativeModuleStringLiteralTypeAnnotation[];
-}
+export type StringLiteralUnionTypeAnnotation =
+  UnionTypeAnnotation<StringLiteralTypeAnnotation>;
+
+export type NumberLiteralUnionTypeAnnotation =
+  UnionTypeAnnotation<NumberLiteralTypeAnnotation>;
+
+export type BooleanLiteralUnionTypeAnnotation =
+  UnionTypeAnnotation<BooleanLiteralTypeAnnotation>;
 
 export interface NativeModuleNumberTypeAnnotation {
   readonly type: 'NumberTypeAnnotation';
@@ -369,15 +404,17 @@ export interface NativeModulePromiseTypeAnnotation {
   readonly elementType: Nullable<NativeModuleBaseTypeAnnotation> | VoidTypeAnnotation;
 }
 
-export type UnionTypeAnnotationMemberType =
-  | 'NumberTypeAnnotation'
-  | 'ObjectTypeAnnotation'
-  | 'StringTypeAnnotation';
+export type NativeModuleUnionTypeAnnotationMemberType =
+  | NativeModuleObjectTypeAnnotation
+  | StringLiteralTypeAnnotation
+  | NumberLiteralTypeAnnotation
+  | BooleanLiteralTypeAnnotation
+  | BooleanTypeAnnotation
+  | StringTypeAnnotation
+  | NumberTypeAnnotation;
 
-export interface NativeModuleUnionTypeAnnotation {
-  readonly type: 'UnionTypeAnnotation';
-  readonly memberType: UnionTypeAnnotationMemberType;
-}
+export type NativeModuleUnionTypeAnnotation =
+  UnionTypeAnnotation<NativeModuleUnionTypeAnnotationMemberType>;
 
 export interface NativeModuleMixedTypeAnnotation {
   readonly type: 'MixedTypeAnnotation';
diff --git a/packages/react-native-codegen/src/CodegenSchema.js b/packages/react-native-codegen/src/CodegenSchema.js
index 99299dafc3c043..d94e410ee5f681 100644
--- a/packages/react-native-codegen/src/CodegenSchema.js
+++ b/packages/react-native-codegen/src/CodegenSchema.js
@@ -30,6 +30,10 @@ export type FloatTypeAnnotation = $ReadOnly<{
   type: 'FloatTypeAnnotation',
 }>;
 
+export type NumberTypeAnnotation = $ReadOnly<{
+  type: 'NumberTypeAnnotation',
+}>;
+
 export type BooleanTypeAnnotation = $ReadOnly<{
   type: 'BooleanTypeAnnotation',
 }>;
@@ -52,11 +56,20 @@ export type StringLiteralTypeAnnotation = $ReadOnly<{
   value: string,
 }>;
 
-export type StringLiteralUnionTypeAnnotation = $ReadOnly<{
-  type: 'StringLiteralUnionTypeAnnotation',
-  types: $ReadOnlyArray<StringLiteralTypeAnnotation>,
+export type BooleanLiteralTypeAnnotation = $ReadOnly<{
+  type: 'BooleanLiteralTypeAnnotation',
+  value: boolean,
 }>;
 
+export type StringLiteralUnionTypeAnnotation =
+  UnionTypeAnnotation<StringLiteralTypeAnnotation>;
+
+export type NumberLiteralUnionTypeAnnotation =
+  UnionTypeAnnotation<NumberLiteralTypeAnnotation>;
+
+export type BooleanLiteralUnionTypeAnnotation =
+  UnionTypeAnnotation<BooleanLiteralTypeAnnotation>;
+
 export type VoidTypeAnnotation = $ReadOnly<{
   type: 'VoidTypeAnnotation',
 }>;
@@ -68,6 +81,18 @@ export type ObjectTypeAnnotation<+T> = $ReadOnly<{
   baseTypes?: $ReadOnlyArray<string>,
 }>;
 
+export type UnionTypeAnnotation<+T> = $ReadOnly<{
+  type: 'UnionTypeAnnotation',
+  types: $ReadOnlyArray<T>,
+}>;
+
+// TODO(T72031674): TupleTypeAnnotation is added for parity with UnionTypeAnnotation
+// to support future implementation. Currently limited to String and Number literals.
+export type TupleTypeAnnotation = $ReadOnly<{
+  type: 'TupleTypeAnnotation',
+  types: StringLiteralTypeAnnotation | NumberLiteralTypeAnnotation,
+}>;
+
 export type MixedTypeAnnotation = $ReadOnly<{
   type: 'MixedTypeAnnotation',
 }>;
@@ -358,15 +383,17 @@ export type NativeModulePromiseTypeAnnotation = $ReadOnly<{
   elementType: VoidTypeAnnotation | Nullable<NativeModuleBaseTypeAnnotation>,
 }>;
 
-export type UnionTypeAnnotationMemberType =
-  | 'NumberTypeAnnotation'
-  | 'ObjectTypeAnnotation'
-  | 'StringTypeAnnotation';
+export type NativeModuleUnionTypeAnnotationMemberType =
+  | NativeModuleObjectTypeAnnotation
+  | StringLiteralTypeAnnotation
+  | NumberLiteralTypeAnnotation
+  | BooleanLiteralTypeAnnotation
+  | BooleanTypeAnnotation
+  | StringTypeAnnotation
+  | NumberTypeAnnotation;
 
-export type NativeModuleUnionTypeAnnotation = $ReadOnly<{
-  type: 'UnionTypeAnnotation',
-  memberType: UnionTypeAnnotationMemberType,
-}>;
+export type NativeModuleUnionTypeAnnotation =
+  UnionTypeAnnotation<NativeModuleUnionTypeAnnotationMemberType>;
 
 export type NativeModuleMixedTypeAnnotation = $ReadOnly<{
   type: 'MixedTypeAnnotation',
@@ -396,6 +423,7 @@ export type NativeModuleBaseTypeAnnotation =
   | StringLiteralUnionTypeAnnotation
   | NativeModuleNumberTypeAnnotation
   | NumberLiteralTypeAnnotation
+  | BooleanLiteralTypeAnnotation
   | Int32TypeAnnotation
   | DoubleTypeAnnotation
   | FloatTypeAnnotation
diff --git a/packages/react-native-codegen/src/generators/Utils.js b/packages/react-native-codegen/src/generators/Utils.js
index da692692daafac..63a9a9dabafdc4 100644
--- a/packages/react-native-codegen/src/generators/Utils.js
+++ b/packages/react-native-codegen/src/generators/Utils.js
@@ -10,6 +10,8 @@
 
 'use strict';
 
+import type {NativeModuleUnionTypeAnnotation} from '../CodegenSchema';
+
 function capitalize(string: string): string {
   return string.charAt(0).toUpperCase() + string.slice(1);
 }
@@ -44,9 +46,58 @@ function getEnumName(moduleName: string, origEnumName: string): string {
   return `${moduleName}${uppercasedPropName}`;
 }
 
+type ValidUnionType = 'boolean' | 'number' | 'object' | 'string';
+const NumberTypes = ['NumberTypeAnnotation', 'NumberLiteralTypeAnnotation'];
+const StringTypes = ['StringTypeAnnotation', 'StringLiteralTypeAnnotation'];
+const ObjectTypes = ['ObjectTypeAnnotation'];
+const BooleanTypes = ['BooleanTypeAnnotation', 'BooleanLiteralTypeAnnotation'];
+const ValidUnionTypes = [
+  ...NumberTypes,
+  ...ObjectTypes,
+  ...StringTypes,
+  ...BooleanTypes,
+];
+
+function parseValidUnionType(
+  annotation: NativeModuleUnionTypeAnnotation,
+): ValidUnionType {
+  const isUnionOfType = (types: $ReadOnlyArray<string>): boolean => {
+    return annotation.types.every(memberTypeAnnotation =>
+      types.includes(memberTypeAnnotation.type),
+    );
+  };
+  if (isUnionOfType(BooleanTypes)) {
+    return 'boolean';
+  }
+  if (isUnionOfType(NumberTypes)) {
+    return 'number';
+  }
+  if (isUnionOfType(ObjectTypes)) {
+    return 'object';
+  }
+  if (isUnionOfType(StringTypes)) {
+    return 'string';
+  }
+
+  const invalidTypes = annotation.types.filter(member => {
+    return !ValidUnionTypes.includes(member.type);
+  });
+
+  // Check if union members are all supported but not homogeneous
+  // (e.g., mix of number and boolean)
+  if (invalidTypes.length === 0) {
+    throw new Error(`Non-homogenous union member types`);
+  } else {
+    throw new Error(
+      `Unsupported union member types: ${invalidTypes.join(', ')}"`,
+    );
+  }
+}
+
 module.exports = {
   capitalize,
   indent,
+  parseValidUnionType,
   toPascalCase,
   toSafeCppString,
   getEnumName,
diff --git a/packages/react-native-codegen/src/generators/components/CppHelpers.js b/packages/react-native-codegen/src/generators/components/CppHelpers.js
index fa3d56629fec56..e4a1f5bdcc37be 100644
--- a/packages/react-native-codegen/src/generators/components/CppHelpers.js
+++ b/packages/react-native-codegen/src/generators/components/CppHelpers.js
@@ -12,11 +12,23 @@
 import type {
   EventTypeAnnotation,
   NamedShape,
+  NativeModuleUnionTypeAnnotation,
   PropTypeAnnotation,
 } from '../../CodegenSchema';
 
 const {getEnumName, toSafeCppString} = require('../Utils');
 
+const NumberTypes = ['NumberTypeAnnotation', 'NumberLiteralTypeAnnotation'];
+const StringTypes = ['StringTypeAnnotation', 'StringLiteralTypeAnnotation'];
+const ObjectTypes = ['ObjectTypeAnnotation'];
+const BooleanTypes = ['BooleanTypeAnnotation', 'BooleanLiteralTypeAnnotation'];
+const ValidUnionTypes = [
+  ...NumberTypes,
+  ...ObjectTypes,
+  ...StringTypes,
+  ...BooleanTypes,
+];
+
 function toIntEnumValueName(propName: string, value: number): string {
   return `${toSafeCppString(propName)}${value}`;
 }
@@ -61,7 +73,54 @@ function getCppArrayTypeForAnnotation(
     case 'Int32TypeAnnotation':
     case 'MixedTypeAnnotation':
       return `std::vector<${getCppTypeForAnnotation(typeElement.type)}>`;
-    case 'StringLiteralUnionTypeAnnotation':
+    case 'UnionTypeAnnotation':
+      const union: NativeModuleUnionTypeAnnotation = typeElement;
+      const isUnionOfType = (types: $ReadOnlyArray<string>): boolean => {
+        return union.types.every(memberTypeAnnotation =>
+          types.includes(memberTypeAnnotation.type),
+        );
+      };
+
+      if (isUnionOfType(NumberTypes)) {
+        return `std::vector<${getCppTypeForAnnotation('DoubleTypeAnnotation')}>`;
+      }
+
+      if (isUnionOfType(ObjectTypes)) {
+        if (!structParts) {
+          throw new Error(
+            `Trying to generate the event emitter for an Array of ${typeElement.type} without informations to generate the generic type`,
+          );
+        }
+        return `std::vector<${generateEventStructName(structParts)}>`;
+      }
+
+      if (isUnionOfType(['StringTypeAnnotation'])) {
+        return `std::vector<${getCppTypeForAnnotation('StringTypeAnnotation')}>`;
+      }
+      if (isUnionOfType(['StringLiteralTypeAnnotation'])) {
+        if (!structParts) {
+          throw new Error(
+            `Trying to generate the event emitter for an Array of ${typeElement.type} without informations to generate the generic type`,
+          );
+        }
+        return `std::vector<${generateEventStructName(structParts)}>`;
+      }
+
+      if (isUnionOfType(BooleanTypes)) {
+        return `std::vector<${getCppTypeForAnnotation('BooleanTypeAnnotation')}>`;
+      }
+
+      const invalidTypes = union.types.filter(member => {
+        return !ValidUnionTypes.includes(member.type);
+      });
+
+      if (invalidTypes.length === 0) {
+        throw new Error(`Non-homogenous union member types`);
+      } else {
+        throw new Error(
+          `Unsupported union member types: ${invalidTypes.join(', ')}`,
+        );
+      }
     case 'ObjectTypeAnnotation':
       if (!structParts) {
         throw new Error(
diff --git a/packages/react-native-codegen/src/generators/components/GenerateEventEmitterCpp.js b/packages/react-native-codegen/src/generators/components/GenerateEventEmitterCpp.js
index 6d9b72cd2909ae..a890b238c675aa 100644
--- a/packages/react-native-codegen/src/generators/components/GenerateEventEmitterCpp.js
+++ b/packages/react-native-codegen/src/generators/components/GenerateEventEmitterCpp.js
@@ -207,7 +207,7 @@ function handleArrayElementType(
         loopLocalVariable,
         val => `jsi::valueFromDynamic(runtime, ${val})`,
       );
-    case 'StringLiteralUnionTypeAnnotation':
+    case 'UnionTypeAnnotation':
       return setValueAtIndex(
         propertyName,
         indexVariable,
@@ -320,7 +320,7 @@ function generateSetters(
             usingEvent,
             prop => `jsi::valueFromDynamic(runtime, ${prop})`,
           );
-        case 'StringLiteralUnionTypeAnnotation':
+        case 'UnionTypeAnnotation':
           return generateSetter(
             parentPropertyName,
             eventProperty.name,
diff --git a/packages/react-native-codegen/src/generators/components/GenerateEventEmitterH.js b/packages/react-native-codegen/src/generators/components/GenerateEventEmitterH.js
index 0c3468dbc61c81..0546b13f6a8f52 100644
--- a/packages/react-native-codegen/src/generators/components/GenerateEventEmitterH.js
+++ b/packages/react-native-codegen/src/generators/components/GenerateEventEmitterH.js
@@ -128,7 +128,7 @@ function getNativeTypeFromAnnotation(
     case 'FloatTypeAnnotation':
     case 'MixedTypeAnnotation':
       return getCppTypeForAnnotation(type);
-    case 'StringLiteralUnionTypeAnnotation':
+    case 'UnionTypeAnnotation':
     case 'ObjectTypeAnnotation':
       return generateEventStructName([...nameParts, eventProperty.name]);
     case 'ArrayTypeAnnotation':
@@ -188,7 +188,7 @@ function handleGenerateStructForArray(
       nameParts.concat([name]),
       nullthrows(elementType.properties),
     );
-  } else if (elementType.type === 'StringLiteralUnionTypeAnnotation') {
+  } else if (elementType.type === 'UnionTypeAnnotation') {
     generateEnum(
       structs,
       elementType.types.map(literal => literal.value),
@@ -251,7 +251,7 @@ function generateStruct(
           nullthrows(typeAnnotation.properties),
         );
         return;
-      case 'StringLiteralUnionTypeAnnotation':
+      case 'UnionTypeAnnotation':
         generateEnum(
           structs,
           typeAnnotation.types.map(literal => literal.value),
diff --git a/packages/react-native-codegen/src/generators/modules/GenerateModuleH.js b/packages/react-native-codegen/src/generators/modules/GenerateModuleH.js
index 2779f16572e10d..9c85b82a59cb85 100644
--- a/packages/react-native-codegen/src/generators/modules/GenerateModuleH.js
+++ b/packages/react-native-codegen/src/generators/modules/GenerateModuleH.js
@@ -29,7 +29,12 @@ import type {AliasResolver} from './Utils';
 
 const {unwrapNullable} = require('../../parsers/parsers-commons');
 const {wrapOptional} = require('../TypeUtils/Cxx');
-const {getEnumName, toPascalCase, toSafeCppString} = require('../Utils');
+const {
+  getEnumName,
+  parseValidUnionType,
+  toPascalCase,
+  toSafeCppString,
+} = require('../Utils');
 const {
   createAliasResolver,
   getModules,
@@ -92,10 +97,10 @@ function serializeArg(
       return wrap(val => `${val}.asString(rt)`);
     case 'StringLiteralTypeAnnotation':
       return wrap(val => `${val}.asString(rt)`);
-    case 'StringLiteralUnionTypeAnnotation':
-      return wrap(val => `${val}.asString(rt)`);
     case 'BooleanTypeAnnotation':
       return wrap(val => `${val}.asBool()`);
+    case 'BooleanLiteralTypeAnnotation':
+      return wrap(val => `${val}.asBool()`);
     case 'EnumDeclaration':
       switch (realTypeAnnotation.memberType) {
         case 'NumberTypeAnnotation':
@@ -124,17 +129,19 @@ function serializeArg(
     case 'GenericObjectTypeAnnotation':
       return wrap(val => `${val}.asObject(rt)`);
     case 'UnionTypeAnnotation':
-      switch (typeAnnotation.memberType) {
-        case 'NumberTypeAnnotation':
+      const validUnionType = parseValidUnionType(realTypeAnnotation);
+      switch (validUnionType) {
+        case 'boolean':
+          return wrap(val => `${val}.asBool()`);
+        case 'number':
           return wrap(val => `${val}.asNumber()`);
-        case 'ObjectTypeAnnotation':
+        case 'object':
           return wrap(val => `${val}.asObject(rt)`);
-        case 'StringTypeAnnotation':
+        case 'string':
           return wrap(val => `${val}.asString(rt)`);
         default:
-          throw new Error(
-            `Unsupported union member type for param  "${arg.name}, found: ${realTypeAnnotation.memberType}"`,
-          );
+          (validUnionType: empty);
+          throw new Error(`Unsupported union member type`);
       }
     case 'ObjectTypeAnnotation':
       return wrap(val => `${val}.asObject(rt)`);
@@ -251,8 +258,6 @@ function translatePrimitiveJSTypeToCpp(
       return wrapOptional('jsi::String', isRequired);
     case 'StringLiteralTypeAnnotation':
       return wrapOptional('jsi::String', isRequired);
-    case 'StringLiteralUnionTypeAnnotation':
-      return wrapOptional('jsi::String', isRequired);
     case 'NumberTypeAnnotation':
       return wrapOptional('double', isRequired);
     case 'NumberLiteralTypeAnnotation':
@@ -265,6 +270,8 @@ function translatePrimitiveJSTypeToCpp(
       return wrapOptional('int', isRequired);
     case 'BooleanTypeAnnotation':
       return wrapOptional('bool', isRequired);
+    case 'BooleanLiteralTypeAnnotation':
+      return wrapOptional('bool', isRequired);
     case 'EnumDeclaration':
       switch (realTypeAnnotation.memberType) {
         case 'NumberTypeAnnotation':
@@ -277,15 +284,19 @@ function translatePrimitiveJSTypeToCpp(
     case 'GenericObjectTypeAnnotation':
       return wrapOptional('jsi::Object', isRequired);
     case 'UnionTypeAnnotation':
-      switch (typeAnnotation.memberType) {
-        case 'NumberTypeAnnotation':
+      const validUnionType = parseValidUnionType(realTypeAnnotation);
+      switch (validUnionType) {
+        case 'boolean':
+          return wrapOptional('bool', isRequired);
+        case 'number':
           return wrapOptional('double', isRequired);
-        case 'ObjectTypeAnnotation':
+        case 'object':
           return wrapOptional('jsi::Object', isRequired);
-        case 'StringTypeAnnotation':
+        case 'string':
           return wrapOptional('jsi::String', isRequired);
         default:
-          throw new Error(createErrorMessage(realTypeAnnotation.type));
+          (validUnionType: empty);
+          throw new Error(`Unsupported union member type`);
       }
     case 'ObjectTypeAnnotation':
       return wrapOptional('jsi::Object', isRequired);
diff --git a/packages/react-native-codegen/src/generators/modules/GenerateModuleJavaSpec.js b/packages/react-native-codegen/src/generators/modules/GenerateModuleJavaSpec.js
index e634125797cae6..ee55413d361615 100644
--- a/packages/react-native-codegen/src/generators/modules/GenerateModuleJavaSpec.js
+++ b/packages/react-native-codegen/src/generators/modules/GenerateModuleJavaSpec.js
@@ -24,7 +24,7 @@ import type {AliasResolver} from './Utils';
 
 const {unwrapNullable} = require('../../parsers/parsers-commons');
 const {wrapOptional} = require('../TypeUtils/Java');
-const {toPascalCase} = require('../Utils');
+const {parseValidUnionType, toPascalCase} = require('../Utils');
 const {createAliasResolver, getModules} = require('./Utils');
 
 type FilesOutput = Map<string, string>;
@@ -127,14 +127,28 @@ function translateEventEmitterTypeToJavaType(
   eventEmitter: NativeModuleEventEmitterShape,
   imports: Set<string>,
 ): string {
-  const type = eventEmitter.typeAnnotation.typeAnnotation.type;
-  switch (type) {
+  const typeAnnotation = eventEmitter.typeAnnotation.typeAnnotation;
+  switch (typeAnnotation.type) {
     case 'StringTypeAnnotation':
       return 'String';
     case 'StringLiteralTypeAnnotation':
       return 'String';
-    case 'StringLiteralUnionTypeAnnotation':
-      return 'String';
+    case 'UnionTypeAnnotation':
+      const validUnionType = parseValidUnionType(typeAnnotation);
+      switch (validUnionType) {
+        case 'boolean':
+          return 'boolean';
+        case 'number':
+          return 'double';
+        case 'object':
+          imports.add('com.facebook.react.bridge.ReadableMap');
+          return 'ReadableMap';
+        case 'string':
+          return 'String';
+        default:
+          (validUnionType: empty);
+          throw new Error(`Unsupported union member type`);
+      }
     case 'NumberTypeAnnotation':
     case 'NumberLiteralTypeAnnotation':
     case 'FloatTypeAnnotation':
@@ -160,7 +174,7 @@ function translateEventEmitterTypeToJavaType(
         `Unsupported eventType for ${eventEmitter.name}. Found: ${eventEmitter.typeAnnotation.typeAnnotation.type}`,
       );
     default:
-      (type: empty);
+      (typeAnnotation.type: empty);
       throw new Error(
         `Unsupported eventType for ${eventEmitter.name}. Found: ${eventEmitter.typeAnnotation.typeAnnotation.type}`,
       );
@@ -200,8 +214,6 @@ function translateFunctionParamToJavaType(
       return wrapOptional('String', isRequired);
     case 'StringLiteralTypeAnnotation':
       return wrapOptional('String', isRequired);
-    case 'StringLiteralUnionTypeAnnotation':
-      return wrapOptional('String', isRequired);
     case 'NumberTypeAnnotation':
       return wrapOptional('double', isRequired);
     case 'NumberLiteralTypeAnnotation':
@@ -214,6 +226,8 @@ function translateFunctionParamToJavaType(
       return wrapOptional('double', isRequired);
     case 'BooleanTypeAnnotation':
       return wrapOptional('boolean', isRequired);
+    case 'BooleanLiteralTypeAnnotation':
+      return wrapOptional('boolean', isRequired);
     case 'EnumDeclaration':
       switch (realTypeAnnotation.memberType) {
         case 'NumberTypeAnnotation':
@@ -224,18 +238,20 @@ function translateFunctionParamToJavaType(
           throw new Error(createErrorMessage(realTypeAnnotation.type));
       }
     case 'UnionTypeAnnotation':
-      switch (typeAnnotation.memberType) {
-        case 'NumberTypeAnnotation':
+      const validUnionType = parseValidUnionType(realTypeAnnotation);
+      switch (validUnionType) {
+        case 'boolean':
+          return wrapOptional('boolean', isRequired);
+        case 'number':
           return wrapOptional('double', isRequired);
-        case 'ObjectTypeAnnotation':
+        case 'object':
           imports.add('com.facebook.react.bridge.ReadableMap');
           return wrapOptional('ReadableMap', isRequired);
-        case 'StringTypeAnnotation':
+        case 'string':
           return wrapOptional('String', isRequired);
         default:
-          throw new Error(
-            `Unsupported union member returning value, found: ${realTypeAnnotation.memberType}"`,
-          );
+          (validUnionType: empty);
+          throw new Error(`Unsupported union member type`);
       }
     case 'ObjectTypeAnnotation':
       imports.add('com.facebook.react.bridge.ReadableMap');
@@ -296,8 +312,6 @@ function translateFunctionReturnTypeToJavaType(
       return wrapOptional('String', isRequired);
     case 'StringLiteralTypeAnnotation':
       return wrapOptional('String', isRequired);
-    case 'StringLiteralUnionTypeAnnotation':
-      return wrapOptional('String', isRequired);
     case 'NumberTypeAnnotation':
       return wrapOptional('double', isRequired);
     case 'NumberLiteralTypeAnnotation':
@@ -310,6 +324,8 @@ function translateFunctionReturnTypeToJavaType(
       return wrapOptional('double', isRequired);
     case 'BooleanTypeAnnotation':
       return wrapOptional('boolean', isRequired);
+    case 'BooleanLiteralTypeAnnotation':
+      return wrapOptional('boolean', isRequired);
     case 'EnumDeclaration':
       switch (realTypeAnnotation.memberType) {
         case 'NumberTypeAnnotation':
@@ -320,18 +336,20 @@ function translateFunctionReturnTypeToJavaType(
           throw new Error(createErrorMessage(realTypeAnnotation.type));
       }
     case 'UnionTypeAnnotation':
-      switch (realTypeAnnotation.memberType) {
-        case 'NumberTypeAnnotation':
+      const validUnionType = parseValidUnionType(realTypeAnnotation);
+      switch (validUnionType) {
+        case 'boolean':
+          return wrapOptional('boolean', isRequired);
+        case 'number':
           return wrapOptional('double', isRequired);
-        case 'ObjectTypeAnnotation':
+        case 'object':
           imports.add('com.facebook.react.bridge.WritableMap');
-          return wrapOptional('WritableMap', isRequired);
-        case 'StringTypeAnnotation':
+          return wrapOptional('ReadableMap', isRequired);
+        case 'string':
           return wrapOptional('String', isRequired);
         default:
-          throw new Error(
-            `Unsupported union member returning value, found: ${realTypeAnnotation.memberType}"`,
-          );
+          (validUnionType: empty);
+          throw new Error(`Unsupported union member type`);
       }
     case 'ObjectTypeAnnotation':
       imports.add('com.facebook.react.bridge.WritableMap');
@@ -388,6 +406,8 @@ function getFalsyReturnStatementFromReturnType(
       return nullable ? 'return null;' : 'return 0;';
     case 'BooleanTypeAnnotation':
       return nullable ? 'return null;' : 'return false;';
+    case 'BooleanLiteralTypeAnnotation':
+      return nullable ? 'return null;' : 'return false;';
     case 'EnumDeclaration':
       switch (realTypeAnnotation.memberType) {
         case 'NumberTypeAnnotation':
@@ -398,24 +418,24 @@ function getFalsyReturnStatementFromReturnType(
           throw new Error(createErrorMessage(realTypeAnnotation.type));
       }
     case 'UnionTypeAnnotation':
-      switch (realTypeAnnotation.memberType) {
-        case 'NumberTypeAnnotation':
+      const validUnionType = parseValidUnionType(realTypeAnnotation);
+      switch (validUnionType) {
+        case 'boolean':
+          return nullable ? 'return null;' : 'return false;';
+        case 'number':
           return nullable ? 'return null;' : 'return 0;';
-        case 'ObjectTypeAnnotation':
+        case 'object':
           return 'return null;';
-        case 'StringTypeAnnotation':
+        case 'string':
           return nullable ? 'return null;' : 'return "";';
         default:
-          throw new Error(
-            `Unsupported union member returning value, found: ${realTypeAnnotation.memberType}"`,
-          );
+          (validUnionType: empty);
+          throw new Error(`Unsupported union member type`);
       }
     case 'StringTypeAnnotation':
       return nullable ? 'return null;' : 'return "";';
     case 'StringLiteralTypeAnnotation':
       return nullable ? 'return null;' : 'return "";';
-    case 'StringLiteralUnionTypeAnnotation':
-      return nullable ? 'return null;' : 'return "";';
     case 'ObjectTypeAnnotation':
       return 'return null;';
     case 'GenericObjectTypeAnnotation':
diff --git a/packages/react-native-codegen/src/generators/modules/GenerateModuleJniCpp.js b/packages/react-native-codegen/src/generators/modules/GenerateModuleJniCpp.js
index e9ece53f47d867..691c5a30c2e51d 100644
--- a/packages/react-native-codegen/src/generators/modules/GenerateModuleJniCpp.js
+++ b/packages/react-native-codegen/src/generators/modules/GenerateModuleJniCpp.js
@@ -23,6 +23,7 @@ import type {
 import type {AliasResolver} from './Utils';
 
 const {unwrapNullable} = require('../../parsers/parsers-commons');
+const {parseValidUnionType} = require('../Utils');
 const {createAliasResolver, getModules} = require('./Utils');
 
 type FilesOutput = Map<string, string>;
@@ -167,10 +168,10 @@ function translateReturnTypeToKind(
       return 'StringKind';
     case 'StringLiteralTypeAnnotation':
       return 'StringKind';
-    case 'StringLiteralUnionTypeAnnotation':
-      return 'StringKind';
     case 'BooleanTypeAnnotation':
       return 'BooleanKind';
+    case 'BooleanLiteralTypeAnnotation':
+      return 'BooleanKind';
     case 'EnumDeclaration':
       switch (typeAnnotation.memberType) {
         case 'NumberTypeAnnotation':
@@ -183,17 +184,19 @@ function translateReturnTypeToKind(
           );
       }
     case 'UnionTypeAnnotation':
-      switch (typeAnnotation.memberType) {
-        case 'NumberTypeAnnotation':
+      const validUnionType = parseValidUnionType(realTypeAnnotation);
+      switch (validUnionType) {
+        case 'boolean':
+          return 'BooleanKind';
+        case 'number':
           return 'NumberKind';
-        case 'ObjectTypeAnnotation':
+        case 'object':
           return 'ObjectKind';
-        case 'StringTypeAnnotation':
+        case 'string':
           return 'StringKind';
         default:
-          throw new Error(
-            `Unsupported union member returning value, found: ${realTypeAnnotation.memberType}"`,
-          );
+          (validUnionType: empty);
+          throw new Error(`Unsupported union member type`);
       }
     case 'NumberTypeAnnotation':
       return 'NumberKind';
@@ -252,10 +255,10 @@ function translateParamTypeToJniType(
       return 'Ljava/lang/String;';
     case 'StringLiteralTypeAnnotation':
       return 'Ljava/lang/String;';
-    case 'StringLiteralUnionTypeAnnotation':
-      return 'Ljava/lang/String;';
     case 'BooleanTypeAnnotation':
       return !isRequired ? 'Ljava/lang/Boolean;' : 'Z';
+    case 'BooleanLiteralTypeAnnotation':
+      return !isRequired ? 'Ljava/lang/Boolean;' : 'Z';
     case 'EnumDeclaration':
       switch (typeAnnotation.memberType) {
         case 'NumberTypeAnnotation':
@@ -268,17 +271,19 @@ function translateParamTypeToJniType(
           );
       }
     case 'UnionTypeAnnotation':
-      switch (typeAnnotation.memberType) {
-        case 'NumberTypeAnnotation':
+      const validUnionType = parseValidUnionType(realTypeAnnotation);
+      switch (validUnionType) {
+        case 'boolean':
+          return !isRequired ? 'Ljava/lang/Boolean;' : 'Z';
+        case 'number':
           return !isRequired ? 'Ljava/lang/Double;' : 'D';
-        case 'ObjectTypeAnnotation':
+        case 'object':
           return 'Lcom/facebook/react/bridge/ReadableMap;';
-        case 'StringTypeAnnotation':
+        case 'string':
           return 'Ljava/lang/String;';
         default:
-          throw new Error(
-            `Unsupported union prop value, found: ${realTypeAnnotation.memberType}"`,
-          );
+          (validUnionType: empty);
+          throw new Error(`Unsupported union member type`);
       }
     case 'NumberTypeAnnotation':
       return !isRequired ? 'Ljava/lang/Double;' : 'D';
@@ -334,10 +339,10 @@ function translateReturnTypeToJniType(
       return 'Ljava/lang/String;';
     case 'StringLiteralTypeAnnotation':
       return 'Ljava/lang/String;';
-    case 'StringLiteralUnionTypeAnnotation':
-      return 'Ljava/lang/String;';
     case 'BooleanTypeAnnotation':
       return nullable ? 'Ljava/lang/Boolean;' : 'Z';
+    case 'BooleanLiteralTypeAnnotation':
+      return nullable ? 'Ljava/lang/Boolean;' : 'Z';
     case 'EnumDeclaration':
       switch (typeAnnotation.memberType) {
         case 'NumberTypeAnnotation':
@@ -350,17 +355,19 @@ function translateReturnTypeToJniType(
           );
       }
     case 'UnionTypeAnnotation':
-      switch (typeAnnotation.memberType) {
-        case 'NumberTypeAnnotation':
+      const validUnionType = parseValidUnionType(realTypeAnnotation);
+      switch (validUnionType) {
+        case 'boolean':
+          return nullable ? 'Ljava/lang/Boolean;' : 'Z';
+        case 'number':
           return nullable ? 'Ljava/lang/Double;' : 'D';
-        case 'ObjectTypeAnnotation':
-          return 'Lcom/facebook/react/bridge/WritableMap;';
-        case 'StringTypeAnnotation':
+        case 'object':
+          return 'Lcom/facebook/react/bridge/ReadableMap;';
+        case 'string':
           return 'Ljava/lang/String;';
         default:
-          throw new Error(
-            `Unsupported union member type, found: ${realTypeAnnotation.memberType}"`,
-          );
+          (validUnionType: empty);
+          throw new Error(`Unsupported union member type`);
       }
     case 'NumberTypeAnnotation':
       return nullable ? 'Ljava/lang/Double;' : 'D';
diff --git a/packages/react-native-codegen/src/generators/modules/GenerateModuleObjCpp/StructCollector.js b/packages/react-native-codegen/src/generators/modules/GenerateModuleObjCpp/StructCollector.js
index db243d9f3024a2..3f46ca9c5da355 100644
--- a/packages/react-native-codegen/src/generators/modules/GenerateModuleObjCpp/StructCollector.js
+++ b/packages/react-native-codegen/src/generators/modules/GenerateModuleObjCpp/StructCollector.js
@@ -11,6 +11,7 @@
 'use strict';
 
 import type {
+  BooleanLiteralTypeAnnotation,
   BooleanTypeAnnotation,
   DoubleTypeAnnotation,
   FloatTypeAnnotation,
@@ -35,7 +36,7 @@ const {
   unwrapNullable,
   wrapNullable,
 } = require('../../../parsers/parsers-commons');
-const {capitalize} = require('../../Utils');
+const {capitalize, parseValidUnionType} = require('../../Utils');
 
 type StructContext = 'CONSTANTS' | 'REGULAR';
 
@@ -65,6 +66,7 @@ export type StructTypeAnnotation =
   | StringLiteralUnionTypeAnnotation
   | NativeModuleNumberTypeAnnotation
   | NumberLiteralTypeAnnotation
+  | BooleanLiteralTypeAnnotation
   | Int32TypeAnnotation
   | DoubleTypeAnnotation
   | FloatTypeAnnotation
@@ -127,27 +129,29 @@ class StructCollector {
       case 'MixedTypeAnnotation':
         throw new Error('Mixed types are unsupported in structs');
       case 'UnionTypeAnnotation':
-        switch (typeAnnotation.memberType) {
-          case 'StringTypeAnnotation':
+        const validUnionType = parseValidUnionType(typeAnnotation);
+        switch (validUnionType) {
+          case 'boolean':
             return wrapNullable(nullable, {
-              type: 'StringTypeAnnotation',
+              type: 'BooleanTypeAnnotation',
             });
-          case 'NumberTypeAnnotation':
+          case 'number':
             return wrapNullable(nullable, {
               type: 'NumberTypeAnnotation',
             });
-          case 'ObjectTypeAnnotation':
+          case 'object':
             // This isn't smart enough to actually know how to generate the
             // options on the native side. So we just treat it as an unknown object type
             return wrapNullable(nullable, {
               type: 'GenericObjectTypeAnnotation',
             });
+          case 'string':
+            return wrapNullable(nullable, {
+              type: 'StringTypeAnnotation',
+            });
           default:
-            (typeAnnotation.memberType: empty);
-            throw new Error(
-              'Union types are unsupported in structs' +
-                JSON.stringify(typeAnnotation),
-            );
+            (validUnionType: empty);
+            throw new Error(`Unsupported union member types`);
         }
       default: {
         return wrapNullable(nullable, typeAnnotation);
diff --git a/packages/react-native-codegen/src/generators/modules/GenerateModuleObjCpp/header/serializeConstantsStruct.js b/packages/react-native-codegen/src/generators/modules/GenerateModuleObjCpp/header/serializeConstantsStruct.js
index 9cee0665e8f396..dcc0e7fff2a4e8 100644
--- a/packages/react-native-codegen/src/generators/modules/GenerateModuleObjCpp/header/serializeConstantsStruct.js
+++ b/packages/react-native-codegen/src/generators/modules/GenerateModuleObjCpp/header/serializeConstantsStruct.js
@@ -19,7 +19,7 @@ const {wrapOptional: wrapCxxOptional} = require('../../../TypeUtils/Cxx');
 const {
   wrapOptional: wrapObjCOptional,
 } = require('../../../TypeUtils/Objective-C');
-const {capitalize} = require('../../../Utils');
+const {capitalize, parseValidUnionType} = require('../../../Utils');
 const {getNamespacedStructName, getSafePropertyName} = require('../Utils');
 
 const StructTemplate = ({
@@ -96,8 +96,21 @@ function toObjCType(
       return 'NSString *';
     case 'StringLiteralTypeAnnotation':
       return 'NSString *';
-    case 'StringLiteralUnionTypeAnnotation':
-      return 'NSString *';
+    case 'UnionTypeAnnotation':
+      const validUnionType = parseValidUnionType(typeAnnotation);
+      switch (validUnionType) {
+        case 'boolean':
+          return wrapCxxOptional('bool', isRequired);
+        case 'number':
+          return wrapCxxOptional('double', isRequired);
+        case 'object':
+          return wrapObjCOptional('id<NSObject>', isRequired);
+        case 'string':
+          return 'NSString *';
+        default:
+          (validUnionType: empty);
+          throw new Error(`Unsupported union member type`);
+      }
     case 'NumberTypeAnnotation':
       return wrapCxxOptional('double', isRequired);
     case 'NumberLiteralTypeAnnotation':
@@ -110,6 +123,8 @@ function toObjCType(
       return wrapCxxOptional('double', isRequired);
     case 'BooleanTypeAnnotation':
       return wrapCxxOptional('bool', isRequired);
+    case 'BooleanLiteralTypeAnnotation':
+      return wrapCxxOptional('bool', isRequired);
     case 'EnumDeclaration':
       switch (typeAnnotation.memberType) {
         case 'NumberTypeAnnotation':
@@ -181,8 +196,21 @@ function toObjCValue(
       return value;
     case 'StringLiteralTypeAnnotation':
       return value;
-    case 'StringLiteralUnionTypeAnnotation':
-      return value;
+    case 'UnionTypeAnnotation':
+      const validUnionType = parseValidUnionType(typeAnnotation);
+      switch (validUnionType) {
+        case 'boolean':
+          return wrapPrimitive('BOOL');
+        case 'number':
+          return wrapPrimitive('double');
+        case 'object':
+          return value;
+        case 'string':
+          return value;
+        default:
+          (validUnionType: empty);
+          throw new Error(`Unsupported union member type`);
+      }
     case 'NumberTypeAnnotation':
       return wrapPrimitive('double');
     case 'NumberLiteralTypeAnnotation':
@@ -195,6 +223,8 @@ function toObjCValue(
       return wrapPrimitive('double');
     case 'BooleanTypeAnnotation':
       return wrapPrimitive('BOOL');
+    case 'BooleanLiteralTypeAnnotation':
+      return wrapPrimitive('BOOL');
     case 'EnumDeclaration':
       switch (typeAnnotation.memberType) {
         case 'NumberTypeAnnotation':
diff --git a/packages/react-native-codegen/src/generators/modules/GenerateModuleObjCpp/header/serializeRegularStruct.js b/packages/react-native-codegen/src/generators/modules/GenerateModuleObjCpp/header/serializeRegularStruct.js
index 9fca06510ad933..f633f909437d02 100644
--- a/packages/react-native-codegen/src/generators/modules/GenerateModuleObjCpp/header/serializeRegularStruct.js
+++ b/packages/react-native-codegen/src/generators/modules/GenerateModuleObjCpp/header/serializeRegularStruct.js
@@ -19,7 +19,7 @@ const {wrapOptional: wrapCxxOptional} = require('../../../TypeUtils/Cxx');
 const {
   wrapOptional: wrapObjCOptional,
 } = require('../../../TypeUtils/Objective-C');
-const {capitalize} = require('../../../Utils');
+const {capitalize, parseValidUnionType} = require('../../../Utils');
 const {getNamespacedStructName, getSafePropertyName} = require('../Utils');
 
 const StructTemplate = ({
@@ -87,8 +87,21 @@ function toObjCType(
       return 'NSString *';
     case 'StringLiteralTypeAnnotation':
       return 'NSString *';
-    case 'StringLiteralUnionTypeAnnotation':
-      return 'NSString *';
+    case 'UnionTypeAnnotation':
+      const validUnionType = parseValidUnionType(typeAnnotation);
+      switch (validUnionType) {
+        case 'boolean':
+          return wrapCxxOptional('bool', isRequired);
+        case 'number':
+          return wrapCxxOptional('double', isRequired);
+        case 'object':
+          return wrapObjCOptional('id<NSObject>', isRequired);
+        case 'string':
+          return 'NSString *';
+        default:
+          (validUnionType: empty);
+          throw new Error(`Unsupported union member type`);
+      }
     case 'NumberTypeAnnotation':
       return wrapCxxOptional('double', isRequired);
     case 'NumberLiteralTypeAnnotation':
@@ -101,6 +114,8 @@ function toObjCType(
       return wrapCxxOptional('double', isRequired);
     case 'BooleanTypeAnnotation':
       return wrapCxxOptional('bool', isRequired);
+    case 'BooleanLiteralTypeAnnotation':
+      return wrapCxxOptional('bool', isRequired);
     case 'EnumDeclaration':
       switch (typeAnnotation.memberType) {
         case 'NumberTypeAnnotation':
@@ -171,8 +186,21 @@ function toObjCValue(
       return RCTBridgingTo('String');
     case 'StringLiteralTypeAnnotation':
       return RCTBridgingTo('String');
-    case 'StringLiteralUnionTypeAnnotation':
-      return RCTBridgingTo('String');
+    case 'UnionTypeAnnotation':
+      const validUnionType = parseValidUnionType(typeAnnotation);
+      switch (validUnionType) {
+        case 'boolean':
+          return RCTBridgingTo('Bool');
+        case 'number':
+          return RCTBridgingTo('Double');
+        case 'object':
+          return value;
+        case 'string':
+          return RCTBridgingTo('String');
+        default:
+          (validUnionType: empty);
+          throw new Error(`Unsupported union member type`);
+      }
     case 'NumberTypeAnnotation':
       return RCTBridgingTo('Double');
     case 'NumberLiteralTypeAnnotation':
@@ -185,6 +213,8 @@ function toObjCValue(
       return RCTBridgingTo('Double');
     case 'BooleanTypeAnnotation':
       return RCTBridgingTo('Bool');
+    case 'BooleanLiteralTypeAnnotation':
+      return RCTBridgingTo('Bool');
     case 'EnumDeclaration':
       switch (typeAnnotation.memberType) {
         case 'NumberTypeAnnotation':
diff --git a/packages/react-native-codegen/src/generators/modules/GenerateModuleObjCpp/serializeEventEmitter.js b/packages/react-native-codegen/src/generators/modules/GenerateModuleObjCpp/serializeEventEmitter.js
index fd1afff066fbf7..42aca1934b5816 100644
--- a/packages/react-native-codegen/src/generators/modules/GenerateModuleObjCpp/serializeEventEmitter.js
+++ b/packages/react-native-codegen/src/generators/modules/GenerateModuleObjCpp/serializeEventEmitter.js
@@ -10,20 +10,33 @@
 
 import type {NativeModuleEventEmitterShape} from '../../../CodegenSchema';
 
-const {toPascalCase} = require('../../Utils');
+const {parseValidUnionType, toPascalCase} = require('../../Utils');
 
 function getEventEmitterTypeObjCType(
   eventEmitter: NativeModuleEventEmitterShape,
 ): string {
-  const type = eventEmitter.typeAnnotation.typeAnnotation.type;
+  const typeAnnotation = eventEmitter.typeAnnotation.typeAnnotation;
 
-  switch (type) {
+  switch (typeAnnotation.type) {
     case 'StringTypeAnnotation':
       return 'NSString *_Nonnull';
     case 'StringLiteralTypeAnnotation':
       return 'NSString *_Nonnull';
-    case 'StringLiteralUnionTypeAnnotation':
-      return 'NSString *_Nonnull';
+    case 'UnionTypeAnnotation':
+      const validUnionType = parseValidUnionType(typeAnnotation);
+      switch (validUnionType) {
+        case 'boolean':
+          return 'BOOL';
+        case 'number':
+          return 'NSNumber *_Nonnull';
+        case 'object':
+          return 'NSDictionary *';
+        case 'string':
+          return 'NSString *_Nonnull';
+        default:
+          (validUnionType: empty);
+          throw new Error(`Unsupported union member type`);
+      }
     case 'NumberTypeAnnotation':
     case 'NumberLiteralTypeAnnotation':
       return 'NSNumber *_Nonnull';
@@ -44,7 +57,7 @@ function getEventEmitterTypeObjCType(
         `Unsupported eventType for ${eventEmitter.name}. Found: ${eventEmitter.typeAnnotation.typeAnnotation.type}`,
       );
     default:
-      (type: empty);
+      (typeAnnotation.type: empty);
       throw new Error(
         `Unsupported eventType for ${eventEmitter.name}. Found: ${eventEmitter.typeAnnotation.typeAnnotation.type}`,
       );
diff --git a/packages/react-native-codegen/src/generators/modules/GenerateModuleObjCpp/serializeMethod.js b/packages/react-native-codegen/src/generators/modules/GenerateModuleObjCpp/serializeMethod.js
index 8e0a56472ff8b3..8a9c76f76f3eb8 100644
--- a/packages/react-native-codegen/src/generators/modules/GenerateModuleObjCpp/serializeMethod.js
+++ b/packages/react-native-codegen/src/generators/modules/GenerateModuleObjCpp/serializeMethod.js
@@ -25,7 +25,7 @@ const {
   wrapNullable,
 } = require('../../../parsers/parsers-commons');
 const {wrapOptional} = require('../../TypeUtils/Objective-C');
-const {capitalize} = require('../../Utils');
+const {capitalize, parseValidUnionType} = require('../../Utils');
 const {getNamespacedStructName} = require('./Utils');
 const invariant = require('invariant');
 
@@ -259,8 +259,21 @@ function getParamObjCType(
       return notStruct(wrapOptional('NSString *', !nullable));
     case 'StringLiteralTypeAnnotation':
       return notStruct(wrapOptional('NSString *', !nullable));
-    case 'StringLiteralUnionTypeAnnotation':
-      return notStruct(wrapOptional('NSString *', !nullable));
+    case 'UnionTypeAnnotation':
+      const validUnionType = parseValidUnionType(structTypeAnnotation);
+      switch (validUnionType) {
+        case 'boolean':
+          return notStruct(isRequired ? 'BOOL' : 'NSNumber *');
+        case 'number':
+          return notStruct(isRequired ? 'double' : 'NSNumber *');
+        case 'object':
+          return notStruct(wrapOptional('NSDictionary *', !nullable));
+        case 'string':
+          return notStruct(wrapOptional('NSString *', !nullable));
+        default:
+          (validUnionType: empty);
+          throw new Error(`Unsupported union member type`);
+      }
     case 'NumberTypeAnnotation':
       return notStruct(isRequired ? 'double' : 'NSNumber *');
     case 'NumberLiteralTypeAnnotation':
@@ -273,6 +286,8 @@ function getParamObjCType(
       return notStruct(isRequired ? 'NSInteger' : 'NSNumber *');
     case 'BooleanTypeAnnotation':
       return notStruct(isRequired ? 'BOOL' : 'NSNumber *');
+    case 'BooleanLiteralTypeAnnotation':
+      return notStruct(isRequired ? 'BOOL' : 'NSNumber *');
     case 'EnumDeclaration':
       switch (typeAnnotation.memberType) {
         case 'NumberTypeAnnotation':
@@ -340,10 +355,6 @@ function getReturnObjCType(
       // TODO: Can NSString * returns not be _Nullable?
       // In the legacy codegen, we don't surround NSSTring * with _Nullable
       return wrapOptional('NSString *', isRequired);
-    case 'StringLiteralUnionTypeAnnotation':
-      // TODO: Can NSString * returns not be _Nullable?
-      // In the legacy codegen, we don't surround NSSTring * with _Nullable
-      return wrapOptional('NSString *', isRequired);
     case 'NumberTypeAnnotation':
       return wrapOptional('NSNumber *', isRequired);
     case 'NumberLiteralTypeAnnotation':
@@ -356,6 +367,8 @@ function getReturnObjCType(
       return wrapOptional('NSNumber *', isRequired);
     case 'BooleanTypeAnnotation':
       return wrapOptional('NSNumber *', isRequired);
+    case 'BooleanLiteralTypeAnnotation':
+      return wrapOptional('NSNumber *', isRequired);
     case 'EnumDeclaration':
       switch (typeAnnotation.memberType) {
         case 'NumberTypeAnnotation':
@@ -368,19 +381,21 @@ function getReturnObjCType(
           );
       }
     case 'UnionTypeAnnotation':
-      switch (typeAnnotation.memberType) {
-        case 'NumberTypeAnnotation':
+      const validUnionType = parseValidUnionType(typeAnnotation);
+      switch (validUnionType) {
+        case 'boolean':
           return wrapOptional('NSNumber *', isRequired);
-        case 'ObjectTypeAnnotation':
+        case 'number':
+          return wrapOptional('NSNumber *', isRequired);
+        case 'object':
           return wrapOptional('NSDictionary *', isRequired);
-        case 'StringTypeAnnotation':
+        case 'string':
           // TODO: Can NSString * returns not be _Nullable?
           // In the legacy codegen, we don't surround NSSTring * with _Nullable
           return wrapOptional('NSString *', isRequired);
         default:
-          throw new Error(
-            `Unsupported union return type for ${methodName}, found: ${typeAnnotation.memberType}"`,
-          );
+          (validUnionType: empty);
+          throw new Error(`Unsupported union member type`);
       }
     case 'GenericObjectTypeAnnotation':
       return wrapOptional('NSDictionary *', isRequired);
@@ -414,8 +429,6 @@ function getReturnJSType(
       return 'StringKind';
     case 'StringLiteralTypeAnnotation':
       return 'StringKind';
-    case 'StringLiteralUnionTypeAnnotation':
-      return 'StringKind';
     case 'NumberTypeAnnotation':
       return 'NumberKind';
     case 'NumberLiteralTypeAnnotation':
@@ -428,6 +441,8 @@ function getReturnJSType(
       return 'NumberKind';
     case 'BooleanTypeAnnotation':
       return 'BooleanKind';
+    case 'BooleanLiteralTypeAnnotation':
+      return 'BooleanKind';
     case 'GenericObjectTypeAnnotation':
       return 'ObjectKind';
     case 'EnumDeclaration':
@@ -442,17 +457,19 @@ function getReturnJSType(
           );
       }
     case 'UnionTypeAnnotation':
-      switch (typeAnnotation.memberType) {
-        case 'NumberTypeAnnotation':
+      const validUnionType = parseValidUnionType(typeAnnotation);
+      switch (validUnionType) {
+        case 'boolean':
+          return 'BooleanKind';
+        case 'number':
           return 'NumberKind';
-        case 'ObjectTypeAnnotation':
+        case 'object':
           return 'ObjectKind';
-        case 'StringTypeAnnotation':
+        case 'string':
           return 'StringKind';
         default:
-          throw new Error(
-            `Unsupported return type for ${methodName}. Found: ${typeAnnotation.type}`,
-          );
+          (validUnionType: empty);
+          throw new Error(`Unsupported union member types`);
       }
     default:
       (typeAnnotation.type: 'MixedTypeAnnotation');
diff --git a/packages/react-native-codegen/src/parsers/errors.js b/packages/react-native-codegen/src/parsers/errors.js
index d86cc1d9ae2ca1..ba5b3604efbc92 100644
--- a/packages/react-native-codegen/src/parsers/errors.js
+++ b/packages/react-native-codegen/src/parsers/errors.js
@@ -10,7 +10,6 @@
 
 'use strict';
 
-import type {UnionTypeAnnotationMemberType} from '../CodegenSchema';
 import type {Parser} from './parser';
 
 export type ParserType = 'Flow' | 'TypeScript';
@@ -337,26 +336,6 @@ class UnsupportedEnumDeclarationParserError extends ParserError {
   }
 }
 
-/**
- * Union parsing errors
- */
-
-class UnsupportedUnionTypeAnnotationParserError extends ParserError {
-  constructor(
-    nativeModuleName: string,
-    arrayElementTypeAST: $FlowFixMe,
-    types: UnionTypeAnnotationMemberType[],
-  ) {
-    super(
-      nativeModuleName,
-      arrayElementTypeAST,
-      `Union members must be of the same type, but multiple types were found ${types.join(
-        ', ',
-      )}'.`,
-    );
-  }
-}
-
 /**
  * Module parsing errors
  */
@@ -460,7 +439,6 @@ module.exports = {
   UnsupportedFunctionParamTypeAnnotationParserError,
   UnsupportedFunctionReturnTypeAnnotationParserError,
   UnsupportedEnumDeclarationParserError,
-  UnsupportedUnionTypeAnnotationParserError,
   UnsupportedModuleEventEmitterTypePropertyParserError,
   UnsupportedModuleEventEmitterPropertyParserError,
   UnsupportedModulePropertyParserError,
diff --git a/packages/react-native-codegen/src/parsers/flow/components/events.js b/packages/react-native-codegen/src/parsers/flow/components/events.js
index ba900707aaae0e..c8f41e125c1b0a 100644
--- a/packages/react-native-codegen/src/parsers/flow/components/events.js
+++ b/packages/react-native-codegen/src/parsers/flow/components/events.js
@@ -115,7 +115,7 @@ function extractArrayElementType(
       };
     case 'UnionTypeAnnotation':
       return {
-        type: 'StringLiteralUnionTypeAnnotation',
+        type: 'UnionTypeAnnotation',
         types: typeAnnotation.types.map(option => ({
           type: 'StringLiteralTypeAnnotation',
           value: parser.getLiteralValue(option),
diff --git a/packages/react-native-codegen/src/parsers/flow/modules/index.js b/packages/react-native-codegen/src/parsers/flow/modules/index.js
index 51972f39ae03f6..33d858d8ba8a77 100644
--- a/packages/react-native-codegen/src/parsers/flow/modules/index.js
+++ b/packages/react-native-codegen/src/parsers/flow/modules/index.js
@@ -244,7 +244,18 @@ function translateTypeAnnotation(
       );
     }
     case 'UnionTypeAnnotation': {
-      return emitUnion(nullable, hasteModuleName, typeAnnotation, parser);
+      return emitUnion(
+        nullable,
+        hasteModuleName,
+        typeAnnotation,
+        types,
+        aliasMap,
+        enumMap,
+        tryParse,
+        cxxOnly,
+        translateTypeAnnotation,
+        parser,
+      );
     }
     case 'NumberLiteralTypeAnnotation': {
       return emitNumberLiteral(nullable, typeAnnotation.value);
diff --git a/packages/react-native-codegen/src/parsers/flow/parser.js b/packages/react-native-codegen/src/parsers/flow/parser.js
index c8224d4e44e729..d251d7976dbcd5 100644
--- a/packages/react-native-codegen/src/parsers/flow/parser.js
+++ b/packages/react-native-codegen/src/parsers/flow/parser.js
@@ -18,10 +18,10 @@ import type {
   NativeModuleEnumMember,
   NativeModuleEnumMemberType,
   NativeModuleParamTypeAnnotation,
+  NativeModuleUnionTypeAnnotationMemberType,
   Nullable,
   PropTypeAnnotation,
   SchemaType,
-  UnionTypeAnnotationMemberType,
 } from '../../CodegenSchema';
 import type {ParserType} from '../errors';
 import type {
@@ -111,7 +111,7 @@ class FlowParser implements Parser {
 
   remapUnionTypeAnnotationMemberNames(
     membersTypes: $FlowFixMe[],
-  ): UnionTypeAnnotationMemberType[] {
+  ): NativeModuleUnionTypeAnnotationMemberType[] {
     const remapLiteral = (item: $FlowFixMe) => {
       return item.type
         .replace('NumberLiteralTypeAnnotation', 'NumberTypeAnnotation')
@@ -121,12 +121,6 @@ class FlowParser implements Parser {
     return [...new Set(membersTypes.map(remapLiteral))];
   }
 
-  getStringLiteralUnionTypeAnnotationStringLiterals(
-    membersTypes: $FlowFixMe[],
-  ): string[] {
-    return membersTypes.map((item: $FlowFixMe) => item.value);
-  }
-
   parseFile(filename: string): SchemaType {
     const contents = fs.readFileSync(filename, 'utf8');
 
diff --git a/packages/react-native-codegen/src/parsers/parser.js b/packages/react-native-codegen/src/parsers/parser.js
index f151fd1e2f7248..4e25ed6495c5ef 100644
--- a/packages/react-native-codegen/src/parsers/parser.js
+++ b/packages/react-native-codegen/src/parsers/parser.js
@@ -18,10 +18,10 @@ import type {
   NativeModuleEnumMember,
   NativeModuleEnumMemberType,
   NativeModuleParamTypeAnnotation,
+  NativeModuleUnionTypeAnnotationMemberType,
   Nullable,
   PropTypeAnnotation,
   SchemaType,
-  UnionTypeAnnotationMemberType,
 } from '../CodegenSchema';
 import type {ParserType} from './errors';
 import type {
@@ -146,15 +146,7 @@ export interface Parser {
    */
   remapUnionTypeAnnotationMemberNames(
     types: $FlowFixMe,
-  ): UnionTypeAnnotationMemberType[];
-  /**
-   * Given a union annotation members types, it returns an array of string literals.
-   * @parameter membersTypes: union annotation members types
-   * @returns: an array of string literals.
-   */
-  getStringLiteralUnionTypeAnnotationStringLiterals(
-    types: $FlowFixMe,
-  ): string[];
+  ): NativeModuleUnionTypeAnnotationMemberType[];
   /**
    * Given the name of a file, it returns a Schema.
    * @parameter filename: the name of the file.
diff --git a/packages/react-native-codegen/src/parsers/parserMock.js b/packages/react-native-codegen/src/parsers/parserMock.js
index 7b22d8a0a5e97c..5ce04ca1139697 100644
--- a/packages/react-native-codegen/src/parsers/parserMock.js
+++ b/packages/react-native-codegen/src/parsers/parserMock.js
@@ -18,10 +18,10 @@ import type {
   NativeModuleEnumMember,
   NativeModuleEnumMemberType,
   NativeModuleParamTypeAnnotation,
+  NativeModuleUnionTypeAnnotationMemberType,
   Nullable,
   PropTypeAnnotation,
   SchemaType,
-  UnionTypeAnnotationMemberType,
 } from '../CodegenSchema';
 import type {ParserType} from './errors';
 import type {
@@ -105,13 +105,7 @@ export class MockedParser implements Parser {
 
   remapUnionTypeAnnotationMemberNames(
     membersTypes: $FlowFixMe[],
-  ): UnionTypeAnnotationMemberType[] {
-    return [];
-  }
-
-  getStringLiteralUnionTypeAnnotationStringLiterals(
-    membersTypes: $FlowFixMe[],
-  ): string[] {
+  ): NativeModuleUnionTypeAnnotationMemberType[] {
     return [];
   }
 
diff --git a/packages/react-native-codegen/src/parsers/parsers-primitives.js b/packages/react-native-codegen/src/parsers/parsers-primitives.js
index 27097a0b0b6f09..3dd4b5bf5e4743 100644
--- a/packages/react-native-codegen/src/parsers/parsers-primitives.js
+++ b/packages/react-native-codegen/src/parsers/parsers-primitives.js
@@ -30,12 +30,12 @@ import type {
   NativeModuleTypeAliasTypeAnnotation,
   NativeModuleTypeAnnotation,
   NativeModuleUnionTypeAnnotation,
+  NativeModuleUnionTypeAnnotationMemberType,
   Nullable,
   NumberLiteralTypeAnnotation,
   ObjectTypeAnnotation,
   ReservedTypeAnnotation,
   StringLiteralTypeAnnotation,
-  StringLiteralUnionTypeAnnotation,
   StringTypeAnnotation,
   VoidTypeAnnotation,
 } from '../CodegenSchema';
@@ -51,11 +51,7 @@ const {
   throwIfPartialNotAnnotatingTypeParameter,
   throwIfPartialWithMoreParameter,
 } = require('./error-utils');
-const {
-  ParserError,
-  UnsupportedTypeAnnotationParserError,
-  UnsupportedUnionTypeAnnotationParserError,
-} = require('./errors');
+const {ParserError, UnsupportedTypeAnnotationParserError} = require('./errors');
 const {
   assertGenericTypeAnnotationHasExactlyOneTypeParameter,
   translateFunctionTypeAnnotation,
@@ -420,61 +416,50 @@ function emitUnion(
   nullable: boolean,
   hasteModuleName: string,
   typeAnnotation: $FlowFixMe,
+  types: TypeDeclarationMap,
+  aliasMap: {...NativeModuleAliasMap},
+  enumMap: {...NativeModuleEnumMap},
+  tryParse: ParserErrorCapturer,
+  cxxOnly: boolean,
+  translateTypeAnnotation: $FlowFixMe,
   parser: Parser,
-): Nullable<
-  NativeModuleUnionTypeAnnotation | StringLiteralUnionTypeAnnotation,
-> {
-  // Get all the literals by type
-  // Verify they are all the same
-  // If string, persist as StringLiteralUnionType
-  // If number, persist as NumberTypeAnnotation (TODO: Number literal)
-
-  const unionTypes = parser.remapUnionTypeAnnotationMemberNames(
-    typeAnnotation.types,
+): Nullable<NativeModuleUnionTypeAnnotation> {
+  const unparsedMemberTypes: $ReadOnlyArray<$FlowFixMe> =
+    (typeAnnotation.types: $ReadOnlyArray<$FlowFixMe>);
+
+  const memberTypes = unparsedMemberTypes.map(
+    (memberType: $FlowFixMe): NativeModuleUnionTypeAnnotationMemberType => {
+      switch (memberType.type) {
+        case 'NumberLiteralTypeAnnotation':
+        case 'StringLiteralTypeAnnotation':
+        case 'BooleanLiteralTypeAnnotation':
+        case 'TSLiteralType':
+        case 'GenericTypeAnnotation':
+        case 'TSTypeLiteral':
+        case 'ObjectTypeAnnotation':
+          return translateTypeAnnotation(
+            hasteModuleName,
+            memberType,
+            types,
+            aliasMap,
+            enumMap,
+            tryParse,
+            cxxOnly,
+            parser,
+          );
+        default:
+          throw new UnsupportedTypeAnnotationParserError(
+            hasteModuleName,
+            memberType,
+            parser.language(),
+          );
+      }
+    },
   );
 
-  // Only support unionTypes of the same kind
-  if (unionTypes.length > 1) {
-    throw new UnsupportedUnionTypeAnnotationParserError(
-      hasteModuleName,
-      typeAnnotation,
-      unionTypes,
-    );
-  }
-
-  if (unionTypes[0] === 'StringTypeAnnotation') {
-    // Reprocess as a string literal union
-    return emitStringLiteralUnion(
-      nullable,
-      hasteModuleName,
-      typeAnnotation,
-      parser,
-    );
-  }
-
   return wrapNullable(nullable, {
     type: 'UnionTypeAnnotation',
-    memberType: unionTypes[0],
-  });
-}
-
-function emitStringLiteralUnion(
-  nullable: boolean,
-  hasteModuleName: string,
-  typeAnnotation: $FlowFixMe,
-  parser: Parser,
-): Nullable<StringLiteralUnionTypeAnnotation> {
-  const stringLiterals =
-    parser.getStringLiteralUnionTypeAnnotationStringLiterals(
-      typeAnnotation.types,
-    );
-
-  return wrapNullable(nullable, {
-    type: 'StringLiteralUnionTypeAnnotation',
-    types: stringLiterals.map(stringLiteral => ({
-      type: 'StringLiteralTypeAnnotation',
-      value: stringLiteral,
-    })),
+    types: memberTypes,
   });
 }
 
@@ -752,7 +737,7 @@ function emitUnionProp(
     name,
     optional,
     typeAnnotation: {
-      type: 'StringLiteralUnionTypeAnnotation',
+      type: 'UnionTypeAnnotation',
       types: typeAnnotation.types.map(option => ({
         type: 'StringLiteralTypeAnnotation',
         value: parser.getLiteralValue(option),
diff --git a/packages/react-native-codegen/src/parsers/typescript/components/events.js b/packages/react-native-codegen/src/parsers/typescript/components/events.js
index 1a2e038756bda3..9a97288a98f53e 100644
--- a/packages/react-native-codegen/src/parsers/typescript/components/events.js
+++ b/packages/react-native-codegen/src/parsers/typescript/components/events.js
@@ -127,7 +127,7 @@ function extractArrayElementType(
       };
     case 'TSUnionType':
       return {
-        type: 'StringLiteralUnionTypeAnnotation',
+        type: 'UnionTypeAnnotation',
         types: typeAnnotation.types.map(option => ({
           type: 'StringLiteralTypeAnnotation',
           value: parser.getLiteralValue(option),
diff --git a/packages/react-native-codegen/src/parsers/typescript/modules/index.js b/packages/react-native-codegen/src/parsers/typescript/modules/index.js
index 15f96966660d6b..56573e49645c72 100644
--- a/packages/react-native-codegen/src/parsers/typescript/modules/index.js
+++ b/packages/react-native-codegen/src/parsers/typescript/modules/index.js
@@ -398,7 +398,18 @@ function translateTypeAnnotation(
       );
     }
     case 'TSUnionType': {
-      return emitUnion(nullable, hasteModuleName, typeAnnotation, parser);
+      return emitUnion(
+        nullable,
+        hasteModuleName,
+        typeAnnotation,
+        types,
+        aliasMap,
+        enumMap,
+        tryParse,
+        cxxOnly,
+        translateTypeAnnotation,
+        parser,
+      );
     }
     case 'TSLiteralType': {
       const literal = typeAnnotation.literal;
diff --git a/packages/react-native-codegen/src/parsers/typescript/parser.js b/packages/react-native-codegen/src/parsers/typescript/parser.js
index edbaf368b526e0..60416eb6a1b3ff 100644
--- a/packages/react-native-codegen/src/parsers/typescript/parser.js
+++ b/packages/react-native-codegen/src/parsers/typescript/parser.js
@@ -18,10 +18,10 @@ import type {
   NativeModuleEnumMember,
   NativeModuleEnumMemberType,
   NativeModuleParamTypeAnnotation,
+  NativeModuleUnionTypeAnnotationMemberType,
   Nullable,
   PropTypeAnnotation,
   SchemaType,
-  UnionTypeAnnotationMemberType,
 } from '../../CodegenSchema';
 import type {ParserType} from '../errors';
 import type {
@@ -109,7 +109,7 @@ class TypeScriptParser implements Parser {
 
   remapUnionTypeAnnotationMemberNames(
     membersTypes: Array<$FlowFixMe>,
-  ): Array<UnionTypeAnnotationMemberType> {
+  ): Array<NativeModuleUnionTypeAnnotationMemberType> {
     const remapLiteral = (item: $FlowFixMe) => {
       return item.literal
         ? item.literal.type
@@ -123,12 +123,6 @@ class TypeScriptParser implements Parser {
     return [...new Set(membersTypes.map(remapLiteral))];
   }
 
-  getStringLiteralUnionTypeAnnotationStringLiterals(
-    membersTypes: Array<$FlowFixMe>,
-  ): Array<string> {
-    return membersTypes.map((item: $FlowFixMe) => item.literal.value);
-  }
-
   parseFile(filename: string): SchemaType {
     const contents = fs.readFileSync(filename, 'utf8');