diff --git a/packages/core/src/core/contentGenerator.test.ts b/packages/core/src/core/contentGenerator.test.ts
index 1981f27706..4efd9f65c6 100644
--- a/packages/core/src/core/contentGenerator.test.ts
+++ b/packages/core/src/core/contentGenerator.test.ts
@@ -851,19 +851,6 @@ describe('createContentGenerator', () => {
       ),
     ).rejects.toThrow('Invalid custom base URL: not-a-url');
   });
-
-  it('should reject non-https remote custom baseUrl values', async () => {
-    await expect(
-      createContentGenerator(
-        {
-          apiKey: 'test-api-key',
-          authType: AuthType.USE_GEMINI,
-          baseUrl: 'http://example.com',
-        },
-        mockConfig,
-      ),
-    ).rejects.toThrow('Custom base URL must use HTTPS unless it is localhost.');
-  });
 });
 
 describe('createContentGeneratorConfig', () => {
diff --git a/packages/core/src/core/contentGenerator.ts b/packages/core/src/core/contentGenerator.ts
index 789942bb51..040fed0e9a 100644
--- a/packages/core/src/core/contentGenerator.ts
+++ b/packages/core/src/core/contentGenerator.ts
@@ -110,22 +110,16 @@ export interface VertexAiRoutingConfig {
   sharedRequestType?: VertexAiSharedRequestType;
 }
 
-const LOCAL_HOSTNAMES = ['localhost', '127.0.0.1', '[::1]'];
 const VERTEX_AI_REQUEST_TYPE_HEADER = 'X-Vertex-AI-LLM-Request-Type';
 const VERTEX_AI_SHARED_REQUEST_TYPE_HEADER =
   'X-Vertex-AI-LLM-Shared-Request-Type';
 
 function validateBaseUrl(baseUrl: string): void {
-  let url: URL;
   try {
-    url = new URL(baseUrl);
+    new URL(baseUrl);
   } catch {
     throw new Error(`Invalid custom base URL: ${baseUrl}`);
   }
-
-  if (url.protocol !== 'https:' && !LOCAL_HOSTNAMES.includes(url.hostname)) {
-    throw new Error('Custom base URL must use HTTPS unless it is localhost.');
-  }
 }
 
 export async function createContentGeneratorConfig(