diff --git a/docs/general/getting_started.md b/docs/general/getting_started.md
index ac6d5f79a..b39cd2831 100644
--- a/docs/general/getting_started.md
+++ b/docs/general/getting_started.md
@@ -37,7 +37,7 @@ and
 class CommentSerializer < ActiveModel::Serializer
   attributes :name, :body
 
-  belongs_to :post_id
+  belongs_to :post
 end
 ```