diff --git a/docs/en/getting-started/local_quickstart_go.md b/docs/en/getting-started/local_quickstart_go.md
index b4d53caad7..cacbfb1801 100644
--- a/docs/en/getting-started/local_quickstart_go.md
+++ b/docs/en/getting-started/local_quickstart_go.md
@@ -77,7 +77,11 @@ from Toolbox.
 
 {{< /tab >}}
 
-{{< tab header="ADK Go" lang="go" >}}
+{{< tab header="ADK Go" lang="go" >}} Set your API key (If you don't have an API key yet, you can get one from [Google AI Studio](https://aistudio.google.com/app/apikey).)
+   ```bash
+   export GEMINI_API_KEY="YOUR_ACTUAL_GEMINI_API_KEY"
+   ```
+
 
 {{< include "quickstart/go/adkgo/quickstart.go" >}}