diff --git a/doc/POST_INSTALL.md b/doc/POST_INSTALL.md
index 0e5977b..7f59f50 100644
--- a/doc/POST_INSTALL.md
+++ b/doc/POST_INSTALL.md
@@ -1,4 +1,4 @@
 Congratulation, Open Search is installed!
 
 You may try its API right now. Try this command:
-curl http://localhost:**PORT**
+`curl http://localhost:__PORT__`