diff --git a/packages/cli/src/validateNonInterActiveAuth.test.ts b/packages/cli/src/validateNonInterActiveAuth.test.ts
index 801f4cce..307b20d4 100644
--- a/packages/cli/src/validateNonInterActiveAuth.test.ts
+++ b/packages/cli/src/validateNonInterActiveAuth.test.ts
@@ -15,6 +15,7 @@ describe('validateNonInterActiveAuth', () => {
   let originalEnvGeminiApiKey: string | undefined;
   let originalEnvVertexAi: string | undefined;
   let originalEnvGcp: string | undefined;
+  let originalEnvOpenAiApiKey: string | undefined;
   let consoleErrorSpy: ReturnType<typeof vi.spyOn>;
   let processExitSpy: ReturnType<typeof vi.spyOn>;
   let refreshAuthMock: jest.MockedFunction<
@@ -25,9 +26,11 @@ describe('validateNonInterActiveAuth', () => {
     originalEnvGeminiApiKey = process.env.GEMINI_API_KEY;
     originalEnvVertexAi = process.env.GOOGLE_GENAI_USE_VERTEXAI;
     originalEnvGcp = process.env.GOOGLE_GENAI_USE_GCA;
+    originalEnvOpenAiApiKey = process.env.OPENAI_API_KEY;
     delete process.env.GEMINI_API_KEY;
     delete process.env.GOOGLE_GENAI_USE_VERTEXAI;
     delete process.env.GOOGLE_GENAI_USE_GCA;
+    delete process.env.OPENAI_API_KEY;
     consoleErrorSpy = vi.spyOn(console, 'error').mockImplementation(() => {});
     processExitSpy = vi.spyOn(process, 'exit').mockImplementation((code) => {
       throw new Error(`process.exit(${code}) called`);
@@ -51,6 +54,11 @@ describe('validateNonInterActiveAuth', () => {
     } else {
       delete process.env.GOOGLE_GENAI_USE_GCA;
     }
+    if (originalEnvOpenAiApiKey !== undefined) {
+      process.env.OPENAI_API_KEY = originalEnvOpenAiApiKey;
+    } else {
+      delete process.env.OPENAI_API_KEY;
+    }
     vi.restoreAllMocks();
   });
 
@@ -88,6 +96,15 @@ describe('validateNonInterActiveAuth', () => {
     expect(refreshAuthMock).toHaveBeenCalledWith(AuthType.USE_GEMINI);
   });
 
+  it('uses USE_OPENAI if OPENAI_API_KEY is set', async () => {
+    process.env.OPENAI_API_KEY = 'fake-openai-key';
+    const nonInteractiveConfig: NonInteractiveConfig = {
+      refreshAuth: refreshAuthMock,
+    };
+    await validateNonInteractiveAuth(undefined, nonInteractiveConfig);
+    expect(refreshAuthMock).toHaveBeenCalledWith(AuthType.USE_OPENAI);
+  });
+
   it('uses USE_VERTEX_AI if GOOGLE_GENAI_USE_VERTEXAI is true (with GOOGLE_CLOUD_PROJECT and GOOGLE_CLOUD_LOCATION)', async () => {
     process.env.GOOGLE_GENAI_USE_VERTEXAI = 'true';
     process.env.GOOGLE_CLOUD_PROJECT = 'test-project';
diff --git a/packages/cli/src/validateNonInterActiveAuth.ts b/packages/cli/src/validateNonInterActiveAuth.ts
index 21a0573d..0a974b0e 100644
--- a/packages/cli/src/validateNonInterActiveAuth.ts
+++ b/packages/cli/src/validateNonInterActiveAuth.ts
@@ -18,6 +18,9 @@ function getAuthTypeFromEnv(): AuthType | undefined {
   if (process.env.GEMINI_API_KEY) {
     return AuthType.USE_GEMINI;
   }
+  if (process.env.OPENAI_API_KEY) {
+    return AuthType.USE_OPENAI;
+  }
   return undefined;
 }
 
@@ -29,7 +32,7 @@ export async function validateNonInteractiveAuth(
 
   if (!effectiveAuthType) {
     console.error(
-      `Please set an Auth method in your ${USER_SETTINGS_PATH} or specify one of the following environment variables before running: GEMINI_API_KEY, GOOGLE_GENAI_USE_VERTEXAI, GOOGLE_GENAI_USE_GCA`,
+      `Please set an Auth method in your ${USER_SETTINGS_PATH} or specify one of the following environment variables before running: GEMINI_API_KEY, OPENAI_API_KEY, GOOGLE_GENAI_USE_VERTEXAI, GOOGLE_GENAI_USE_GCA`,
     );
     process.exit(1);
   }