diff --git a/README.md b/README.md
index 891e63a81..105663c23 100644
--- a/README.md
+++ b/README.md
@@ -1080,7 +1080,7 @@ When using Docker, you can pass the read-only mode as an environment variable:
 ```bash
 docker run -i --rm \
   -e GITHUB_PERSONAL_ACCESS_TOKEN=<your-token> \
-  -e GITHUB_READ_ONLY=1 \
+  -e GITHUB_READ-ONLY=1 \
   ghcr.io/github/github-mcp-server
 ```