diff --git a/.changeset/tame-carpets-bake.md b/.changeset/tame-carpets-bake.md
new file mode 100644
index 00000000000..69141ac4ca8
--- /dev/null
+++ b/.changeset/tame-carpets-bake.md
@@ -0,0 +1,5 @@
+---
+"roo-cline": patch
+---
+
+Add credentials auth for Google vertex
diff --git a/src/api/providers/vertex.ts b/src/api/providers/vertex.ts
index 7f764a9076a..bc888e04599 100644
--- a/src/api/providers/vertex.ts
+++ b/src/api/providers/vertex.ts
@@ -11,6 +11,7 @@ import { BaseProvider } from "./base-provider"
 
 import { ANTHROPIC_DEFAULT_MAX_TOKENS } from "./constants"
 import { getModelParams, SingleCompletionHandler } from "../"
+import { GoogleAuth } from "google-auth-library"
 
 // Types for Vertex SDK
 
@@ -120,16 +121,56 @@ export class VertexHandler extends BaseProvider implements SingleCompletionHandl
 			throw new Error(`Unknown model ID: ${this.options.apiModelId}`)
 		}
 
-		this.anthropicClient = new AnthropicVertex({
-			projectId: this.options.vertexProjectId ?? "not-provided",
-			// https://cloud.google.com/vertex-ai/generative-ai/docs/partner-models/use-claude#regions
-			region: this.options.vertexRegion ?? "us-east5",
-		})
+		if (this.options.vertexJsonCredentials) {
+			this.anthropicClient = new AnthropicVertex({
+				projectId: this.options.vertexProjectId ?? "not-provided",
+				// https://cloud.google.com/vertex-ai/generative-ai/docs/partner-models/use-claude#regions
+				region: this.options.vertexRegion ?? "us-east5",
+				googleAuth: new GoogleAuth({
+					scopes: ["https://www.googleapis.com/auth/cloud-platform"],
+					credentials: JSON.parse(this.options.vertexJsonCredentials),
+				}),
+			})
+		} else if (this.options.vertexKeyFile) {
+			this.anthropicClient = new AnthropicVertex({
+				projectId: this.options.vertexProjectId ?? "not-provided",
+				// https://cloud.google.com/vertex-ai/generative-ai/docs/partner-models/use-claude#regions
+				region: this.options.vertexRegion ?? "us-east5",
+				googleAuth: new GoogleAuth({
+					scopes: ["https://www.googleapis.com/auth/cloud-platform"],
+					keyFile: this.options.vertexKeyFile,
+				}),
+			})
+		} else {
+			this.anthropicClient = new AnthropicVertex({
+				projectId: this.options.vertexProjectId ?? "not-provided",
+				// https://cloud.google.com/vertex-ai/generative-ai/docs/partner-models/use-claude#regions
+				region: this.options.vertexRegion ?? "us-east5",
+			})
+		}
 
-		this.geminiClient = new VertexAI({
-			project: this.options.vertexProjectId ?? "not-provided",
-			location: this.options.vertexRegion ?? "us-east5",
-		})
+		if (this.options.vertexJsonCredentials) {
+			this.geminiClient = new VertexAI({
+				project: this.options.vertexProjectId ?? "not-provided",
+				location: this.options.vertexRegion ?? "us-east5",
+				googleAuthOptions: {
+					credentials: JSON.parse(this.options.vertexJsonCredentials),
+				},
+			})
+		} else if (this.options.vertexKeyFile) {
+			this.geminiClient = new VertexAI({
+				project: this.options.vertexProjectId ?? "not-provided",
+				location: this.options.vertexRegion ?? "us-east5",
+				googleAuthOptions: {
+					keyFile: this.options.vertexKeyFile,
+				},
+			})
+		} else {
+			this.geminiClient = new VertexAI({
+				project: this.options.vertexProjectId ?? "not-provided",
+				location: this.options.vertexRegion ?? "us-east5",
+			})
+		}
 	}
 
 	private formatMessageForCache(message: Anthropic.Messages.MessageParam, shouldCache: boolean): VertexMessage {
diff --git a/src/shared/api.ts b/src/shared/api.ts
index d066039850b..23a73b24036 100644
--- a/src/shared/api.ts
+++ b/src/shared/api.ts
@@ -39,6 +39,8 @@ export interface ApiHandlerOptions {
 	awspromptCacheId?: string
 	awsProfile?: string
 	awsUseProfile?: boolean
+	vertexKeyFile?: string
+	vertexJsonCredentials?: string
 	vertexProjectId?: string
 	vertexRegion?: string
 	openAiBaseUrl?: string
@@ -97,6 +99,8 @@ export const API_CONFIG_KEYS: GlobalStateKey[] = [
 	// "awspromptCacheId", // NOT exist on GlobalStateKey
 	"awsProfile",
 	"awsUseProfile",
+	"vertexKeyFile",
+	"vertexJsonCredentials",
 	"vertexProjectId",
 	"vertexRegion",
 	"openAiBaseUrl",
diff --git a/src/shared/globalState.ts b/src/shared/globalState.ts
index fd7bd1adb9f..0665586c472 100644
--- a/src/shared/globalState.ts
+++ b/src/shared/globalState.ts
@@ -28,6 +28,8 @@ export const GLOBAL_STATE_KEYS = [
 	"awsUseCrossRegionInference",
 	"awsProfile",
 	"awsUseProfile",
+	"vertexKeyFile",
+	"vertexJsonCredentials",
 	"vertexProjectId",
 	"vertexRegion",
 	"lastShownAnnouncementId",
diff --git a/webview-ui/src/components/settings/ApiOptions.tsx b/webview-ui/src/components/settings/ApiOptions.tsx
index 407a4b4fcce..efbe098186b 100644
--- a/webview-ui/src/components/settings/ApiOptions.tsx
+++ b/webview-ui/src/components/settings/ApiOptions.tsx
@@ -565,7 +565,28 @@ const ApiOptions = ({
 								2. Install the Google Cloud CLI & configure application default credentials.
 							</VSCodeLink>
 						</div>
+						<div>
+							<VSCodeLink
+								href="https://developers.google.com/workspace/guides/create-credentials?hl=en#service-account"
+								className="text-sm">
+								3. Or create a service account with credentials.
+							</VSCodeLink>
+						</div>
 					</div>
+					<VSCodeTextField
+						value={apiConfiguration?.vertexJsonCredentials || ""}
+						style={{ width: "100%" }}
+						onInput={handleInputChange("vertexJsonCredentials")}
+						placeholder="Enter Credentials JSON...">
+						<span className="font-medium">Google Cloud Credentials</span>
+					</VSCodeTextField>
+					<VSCodeTextField
+						value={apiConfiguration?.vertexKeyFile || ""}
+						style={{ width: "100%" }}
+						onInput={handleInputChange("vertexKeyFile")}
+						placeholder="Enter Key File Path...">
+						<span className="font-medium">Google Cloud Key File Path</span>
+					</VSCodeTextField>
 					<VSCodeTextField
 						value={apiConfiguration?.vertexProjectId || ""}
 						onInput={handleInputChange("vertexProjectId")}