diff --git a/docs/others/index.rst b/docs/others/index.rst
index 3d7d47bb1..fb95149cb 100644
--- a/docs/others/index.rst
+++ b/docs/others/index.rst
@@ -11,6 +11,7 @@ Others
     file_explorer
     fragment
     msg
+    observer
     imgfont
     ime_pinyin
     obj_id