diff --git a/free-programming-books-zh.md b/free-programming-books-zh.md
index 2cf9252d..5bb71c60 100644
--- a/free-programming-books-zh.md
+++ b/free-programming-books-zh.md
@@ -97,7 +97,7 @@
 * [Common Lisp 高级编程技术](http://www.ituring.com.cn/minibook/862) (《On Lisp》中文版)
 
 
-## Markdown
+### Markdown
 * [Markdown 快速入门](http://wowubuntu.com/markdown/basic.html)
 * [Markdown 语法说明](http://wowubuntu.com/markdown/)
 * [Markdown 简明教程](http://jianshu.io/p/7bd23251da0a)