diff --git a/doc/fluid/api_cn/api_guides/index.rst b/doc/fluid/api_cn/api_guides/index.rst
index 4235a462788af17292aa72a651cd4c604f76347f..dc8d04ad584f37c68ebae2c30b40bb7bca3b9bd1 100755
--- a/doc/fluid/api_cn/api_guides/index.rst
+++ b/doc/fluid/api_cn/api_guides/index.rst
@@ -3,7 +3,7 @@ API使用指南
 ===========
 
 ..  toctree::
-	:hidden:
+    :hidden:
 
     high_low_level_api.md
     low_level/layers/index.rst