diff --git a/doc/api/v2/config/activation.rst b/doc/api/v2/config/activation.rst
index eca3ce03bcdc599edca802d8dfca48d4f28275a2..5317e66b64bbd85c61f19700a9d2c1d239dee573 100644
--- a/doc/api/v2/config/activation.rst
+++ b/doc/api/v2/config/activation.rst
@@ -99,3 +99,10 @@ STanh
 ..  automodule:: paddle.v2.activation
     :members: STanh
     :noindex:
+    
+SoftSign
+========
+
+..  automodule:: paddle.v2.activation
+    :members: SoftSign
+    :noindex: