diff --git a/llms/googleai/googleai_test.go b/llms/googleai/googleai_test.go
index f8d90098d..7ea3f14f2 100644
--- a/llms/googleai/googleai_test.go
+++ b/llms/googleai/googleai_test.go
@@ -168,6 +168,35 @@ func TestGoogleAIGenerateContentWithSystemMessage(t *testing.T) {
 	assert.NotEmpty(t, resp.Choices)
 }
 
+func TestGoogleAIGenerateContentWithCustomBaseURL(t *testing.T) {
+	// This proves the option is accepted and doesn't break the SDK's path construction.
+	officialBaseURL := "https://generativelanguage.googleapis.com"
+
+	llm := newHTTPRRClient(t, WithBaseURL(officialBaseURL))
+
+	ctx := context.Background()
+	content := []llms.MessageContent{
+		{
+			Role: llms.ChatMessageTypeHuman,
+			Parts: []llms.ContentPart{
+				llms.TextPart("Hey! How are you doing?"),
+			},
+		},
+	}
+
+	resp, err := llm.GenerateContent(ctx, content)
+	if err != nil {
+		// Check if this is a recording mismatch error
+		if strings.Contains(err.Error(), "cached HTTP response not found") {
+			t.Skip("Recording format has changed or is incompatible. Hint: Re-run tests with -httprecord=. to record new HTTP interactions")
+		}
+		require.NoError(t, err)
+	}
+
+	require.NoError(t, err)
+	require.NotNil(t, resp)
+}
+
 func TestGoogleAICall(t *testing.T) {
 
 	llm := newHTTPRRClient(t)
diff --git a/llms/googleai/googleai_unit_test.go b/llms/googleai/googleai_unit_test.go
index ba2186551..d337e9918 100644
--- a/llms/googleai/googleai_unit_test.go
+++ b/llms/googleai/googleai_unit_test.go
@@ -138,6 +138,12 @@ func TestOptions(t *testing.T) { //nolint:funlen // comprehensive test //nolint:
 		assert.Len(t, opts.ClientOptions, 1)
 	})
 
+	t.Run("WithBaseURL", func(t *testing.T) {
+		opts := &Options{}
+		WithBaseURL("https://custom.endpoint.com")(opts)
+		assert.Len(t, opts.ClientOptions, 1)
+	})
+
 	t.Run("WithHTTPClient", func(t *testing.T) {
 		opts := &Options{}
 		WithHTTPClient(nil)(opts)
diff --git a/llms/googleai/option.go b/llms/googleai/option.go
index 6bd41cb42..cfbdfb8de 100644
--- a/llms/googleai/option.go
+++ b/llms/googleai/option.go
@@ -92,6 +92,16 @@ func WithRest() Option {
 	}
 }
 
+// WithBaseURL appends a ClientOption that configures the underlying Google AI
+// client to use a custom base URL (endpoint). This is useful for directing
+// requests to proxy servers, local development environments, or alternative
+// regional endpoints not automatically handled by the default client setup.
+func WithBaseURL(baseURL string) Option {
+	return func(opts *Options) {
+		opts.ClientOptions = append(opts.ClientOptions, option.WithEndpoint(baseURL))
+	}
+}
+
 // WithHTTPClient append a ClientOption that uses the provided HTTP client to
 // make requests.
 // This is useful for vertex clients.
diff --git a/llms/googleai/testdata/TestGoogleAIGenerateContentWithCustomBaseURL.httprr b/llms/googleai/testdata/TestGoogleAIGenerateContentWithCustomBaseURL.httprr
new file mode 100644
index 000000000..390a8a019
--- /dev/null
+++ b/llms/googleai/testdata/TestGoogleAIGenerateContentWithCustomBaseURL.httprr
@@ -0,0 +1,77 @@
+httprr trace v1
+781 1535
+POST https://generativelanguage.googleapis.com/v1beta/models/gemini-2.0-flash:generateContent?%24alt=json%3Benum-encoding%3Dint HTTP/1.1
+Host: generativelanguage.googleapis.com
+User-Agent: langchaingo-httprr
+Content-Length: 362
+Content-Type: application/json
+x-goog-api-client: gl-go/X.XX.X gccl/vX.XX.X genai-go/X.XX.X gapic/X.X.X gax/X.XX.X rest/UNKNOWN
+x-goog-request-params: model=models%2Fgemini-2.0-flash
+
+{"model":"models/gemini-2.0-flash", "contents":[{"parts":[{"text":"Hey! How are you doing?"}], "role":"user"}], "safetySettings":[{"category":10, "threshold":3}, {"category":7, "threshold":3}, {"category":8, "threshold":3}, {"category":9, "threshold":3}], "generationConfig":{"candidateCount":1, "maxOutputTokens":2048, "temperature":0.5, "topP":0.95, "topK":3}}HTTP/2.0 200 OK
+Content-Length: 1156
+Alt-Svc: h3=":443"; ma=2592000,h3-29=":443"; ma=2592000
+Content-Type: application/json; charset=UTF-8
+Date: Sat, 21 Feb 2026 09:05:56 GMT
+Server: scaffolding on HTTPServer2
+Server-Timing: gfet4t7; dur=710
+Vary: Origin
+Vary: X-Origin
+Vary: Referer
+X-Content-Type-Options: nosniff
+X-Frame-Options: SAMEORIGIN
+X-Xss-Protection: 0
+
+{
+  "candidates": [
+    {
+      "content": {
+        "parts": [
+          {
+            "text": "I'm doing well, thank you for asking! As a large language model, I don't experience emotions or feelings like humans do, but I'm functioning optimally and ready to assist you. How can I help you today?\n"
+          }
+        ],
+        "role": "model"
+      },
+      "finishReason": 1,
+      "safetyRatings": [
+        {
+          "category": 8,
+          "probability": 1
+        },
+        {
+          "category": 10,
+          "probability": 1
+        },
+        {
+          "category": 7,
+          "probability": 1
+        },
+        {
+          "category": 9,
+          "probability": 1
+        }
+      ],
+      "avgLogprobs": -0.0772957655848289
+    }
+  ],
+  "usageMetadata": {
+    "promptTokenCount": 7,
+    "candidatesTokenCount": 49,
+    "totalTokenCount": 56,
+    "promptTokensDetails": [
+      {
+        "modality": 1,
+        "tokenCount": 7
+      }
+    ],
+    "candidatesTokensDetails": [
+      {
+        "modality": 1,
+        "tokenCount": 49
+      }
+    ]
+  },
+  "modelVersion": "gemini-2.0-flash",
+  "responseId": "c3WZad6YHraWxN8PgovYIQ"
+}