diff --git a/.changeset/itchy-moments-live.md b/.changeset/itchy-moments-live.md
new file mode 100644
index 0000000000..a3f55ff431
--- /dev/null
+++ b/.changeset/itchy-moments-live.md
@@ -0,0 +1,5 @@
+---
+"sit-onyx": minor
+---
+
+Implemented basic expandable row feature for DataGrid
diff --git a/packages/sit-onyx/src/components/OnyxDataGrid/examples/ExpandableRowExample.vue b/packages/sit-onyx/src/components/OnyxDataGrid/examples/ExpandableRowExample.vue
new file mode 100644
index 0000000000..3239573f77
--- /dev/null
+++ b/packages/sit-onyx/src/components/OnyxDataGrid/examples/ExpandableRowExample.vue
@@ -0,0 +1,34 @@
+<script setup lang="ts">
+import { h } from "vue";
+import { OnyxDataGrid, OnyxHeadline, type ColumnConfig } from "../../../index.js";
+import { useExpandableRows } from "../features/all.js";
+
+type TEntry = {
+  id: number;
+  name: string;
+  age: number;
+};
+
+const data: TEntry[] = [
+  { id: 1, name: "Alice", age: 30 },
+  { id: 2, name: "Charlie", age: 35 },
+  { id: 3, name: "Bob", age: 25 },
+  { id: 4, name: "Robin", age: 28 },
+  { id: 5, name: "John", age: 42 },
+];
+
+const columns: ColumnConfig<TEntry>[] = [
+  { key: "name", label: "Name" },
+  { key: "age", label: "Age", type: "number" },
+];
+
+const features = [
+  useExpandableRows<TEntry>({
+    detailsComponent: (row) => h(OnyxHeadline, { is: "h3" }, () => `Details for ${row.name}`),
+  }),
+];
+</script>
+
+<template>
+  <OnyxDataGrid headline="Example headline" :columns :data :features />
+</template>
diff --git a/packages/sit-onyx/src/components/OnyxDataGrid/examples/OnyxDataGridFeatureExamples.stories.ts b/packages/sit-onyx/src/components/OnyxDataGrid/examples/OnyxDataGridFeatureExamples.stories.ts
index 011d77672e..2d41ca89a3 100644
--- a/packages/sit-onyx/src/components/OnyxDataGrid/examples/OnyxDataGridFeatureExamples.stories.ts
+++ b/packages/sit-onyx/src/components/OnyxDataGrid/examples/OnyxDataGridFeatureExamples.stories.ts
@@ -28,6 +28,10 @@ export const Editing: Story = {
   ...createAdvancedStoryExample("OnyxDataGrid", "EditingExample"),
 };
 
+export const ExpandableRow: Story = {
+  ...createAdvancedStoryExample("OnyxDataGrid", "ExpandableRowExample"),
+};
+
 export const LazyLoading: Story = {
   ...createAdvancedStoryExample("OnyxDataGrid", "LazyLoadingExample"),
 };
diff --git a/packages/sit-onyx/src/components/OnyxDataGrid/features/all.ts b/packages/sit-onyx/src/components/OnyxDataGrid/features/all.ts
index d7da80f05e..437a287388 100644
--- a/packages/sit-onyx/src/components/OnyxDataGrid/features/all.ts
+++ b/packages/sit-onyx/src/components/OnyxDataGrid/features/all.ts
@@ -1,3 +1,4 @@
+export * from "./expandableRows/types.js";
 export * from "./filtering/types.js";
 export * from "./hideColumns/types.js";
 export * from "./pagination/types.js";
@@ -7,6 +8,7 @@ export * from "./sorting/types.js";
 export * from "./stickyColumns/types.js";
 
 export { useEditing } from "./editing/editing.js";
+export { useExpandableRows } from "./expandableRows/expandableRows.js";
 export { useFiltering } from "./filtering/filtering.js";
 export { useHideColumns } from "./hideColumns/hideColumns.js";
 export { usePagination } from "./pagination/pagination.js";
diff --git a/packages/sit-onyx/src/components/OnyxDataGrid/features/expandableRows/expandableRows.ts b/packages/sit-onyx/src/components/OnyxDataGrid/features/expandableRows/expandableRows.ts
new file mode 100644
index 0000000000..8d26bc91a1
--- /dev/null
+++ b/packages/sit-onyx/src/components/OnyxDataGrid/features/expandableRows/expandableRows.ts
@@ -0,0 +1,120 @@
+import { iconChevronDown, iconChevronUp } from "@sit-onyx/icons";
+import { h, ref } from "vue";
+import { DataGridFeatures } from "../../../../index.js";
+import OnyxSystemButton from "../../../OnyxSystemButton/OnyxSystemButton.vue";
+import { DataGridRowOptionsSymbol, type DataGridEntry } from "../../types.js";
+import { createFeature, type DataGridFeature, type InternalColumnConfig } from "../index.js";
+import type { UseExpandableRowsOptions } from "./types.js";
+
+const EXPANDABLE_ROWS_FEATURE = Symbol("ExpandableRowsFeature");
+const EXPAND_BUTTON_COLUMN = Symbol("ExpandButtonColumn");
+const EXPAND_BUTTON_RENDERER = Symbol("ExpandButtonRenderer");
+const DETAILS_COLUMN = Symbol("DetailsColumn");
+const DETAILS_RENDERER = Symbol("DetailsRenderer");
+
+export const useExpandableRows = <TEntry extends DataGridEntry>(
+  options: UseExpandableRowsOptions<TEntry>,
+) =>
+  createFeature(() => {
+    const columnConfig = ref<Readonly<InternalColumnConfig<TEntry>[]>>([]);
+
+    const expandedRows = ref<Set<PropertyKey>>(new Set());
+    const toggleExpanded = (id: PropertyKey) => {
+      if (expandedRows.value.has(id)) {
+        expandedRows.value.delete(id);
+      } else {
+        expandedRows.value.add(id);
+      }
+    };
+
+    /**
+     * Adds the detail row for expandedd columns
+     */
+    const mapRow = (row: TEntry) => {
+      if (!expandedRows.value.has(row.id))
+        return [
+          // don't change anything
+          {
+            ...row,
+            [DataGridRowOptionsSymbol]: {
+              columns: columnConfig.value,
+            },
+          },
+        ];
+      else
+        return [
+          {
+            ...row,
+            [DataGridRowOptionsSymbol]: {
+              columns: columnConfig.value,
+            },
+          },
+          // add hidden row to keep striped pattern
+          {
+            [DataGridRowOptionsSymbol]: {
+              trAttributes: {
+                style: { display: "none" },
+              },
+            },
+          },
+          // add row for details
+          {
+            ...row,
+            id: row.id,
+            [DataGridRowOptionsSymbol]: {
+              columns: [{ key: DETAILS_COLUMN, type: { name: DETAILS_RENDERER } }],
+            },
+          },
+        ];
+    };
+
+    return {
+      name: EXPANDABLE_ROWS_FEATURE,
+      watch: [expandedRows, columnConfig],
+      modifyColumns: {
+        func: (cols) => {
+          const config = [
+            {
+              key: EXPAND_BUTTON_COLUMN,
+              label: "",
+              type: { name: EXPAND_BUTTON_RENDERER },
+              width: "min-content",
+            },
+            ...cols,
+          ] as InternalColumnConfig<TEntry>[];
+
+          // Store the column configuration with column for expand button for later reference
+          columnConfig.value = config;
+          return config;
+        },
+      },
+      mutation: {
+        func: (rows) => {
+          return rows.flatMap(mapRow);
+        },
+      },
+
+      typeRenderer: {
+        [EXPAND_BUTTON_RENDERER]: DataGridFeatures.createTypeRenderer<object, TEntry>({
+          cell: {
+            component: ({ row }) =>
+              h(OnyxSystemButton, {
+                icon: expandedRows.value.has(row.id) ? iconChevronUp : iconChevronDown,
+                label: "",
+                onClick: () => {
+                  toggleExpanded(row.id);
+                },
+              }),
+          },
+        }),
+        [DETAILS_RENDERER]: DataGridFeatures.createTypeRenderer<object, TEntry>({
+          cell: {
+            tdAttributes: {
+              colspan: 99,
+            },
+            component: ({ row }) => options.detailsComponent(row),
+          },
+        }),
+      },
+    };
+  }) as DataGridFeature<TEntry>;
diff --git a/packages/sit-onyx/src/components/OnyxDataGrid/features/expandableRows/types.ts b/packages/sit-onyx/src/components/OnyxDataGrid/features/expandableRows/types.ts
new file mode 100644
index 0000000000..b598119325
--- /dev/null
+++ b/packages/sit-onyx/src/components/OnyxDataGrid/features/expandableRows/types.ts
@@ -0,0 +1,11 @@
+import type { Component } from "vue";
+
+/**
+ * Options for rendering detail content for expanded rows.
+ */
+export type UseExpandableRowsOptions<TEntry> = {
+  /**
+   * Function to render the detail content.
+   */
+  detailsComponent: (row: TEntry) => Component;
+};