diff --git a/README.md b/README.md
index 8c48db9..f5890a5 100644
--- a/README.md
+++ b/README.md
@@ -17,7 +17,7 @@ $ gem install jekyll-responsive_image
 Then you can either add it to the `gems` section of your `_config.yml`:
 
 ```yaml
-gems: [jekyll/responsive-image]
+gems: [jekyll/responsive_image]
 ```
 
 Or you can copy the contents of [`responsive_image.rb`](lib/jekyll/responsive_image.rb) into your `_plugins` directory.