diff --git a/python/paddle/fluid/param_attr.py b/python/paddle/fluid/param_attr.py
index 4105d5c1a4e49821e7da3423271e2b67b030936b..65f7bd64708125e0c31a9ac3c6a8d1ea3de9e8f6 100644
--- a/python/paddle/fluid/param_attr.py
+++ b/python/paddle/fluid/param_attr.py
@@ -56,7 +56,7 @@ class ParamAttr(object):
                 no regularization.
         trainable (bool): Whether this parameter is trainable. Default True.
         do_model_average (bool): Whether this parameter should do model average
-                when model average is enabled. Default False.
+                when model average is enabled. Only used in ExponentialMovingAverage. Default True.
         need_clip (bool): Whether the parameter gradient need to be cliped in optimizer. Default is True.
 
     Examples: