diff --git a/docs/developer_guides/chap04_message_stream.md b/docs/developer_guides/chap04_message_stream.md
index 265ebd1fc3..aa459d85c0 100644
--- a/docs/developer_guides/chap04_message_stream.md
+++ b/docs/developer_guides/chap04_message_stream.md
@@ -251,10 +251,6 @@ type RmsFactory struct {
 
 
 ```go
-// PulsarMsgStream
-
-func (f *PmsFactory) NewMsgStream(ctx context.Context) (MsgStream, error)
-