diff --git a/python/paddle/fluid/incubate/fleet/collective/__init__.py b/python/paddle/fluid/incubate/fleet/collective/__init__.py
index 26b8e2c3b12a0a2e888377ddad24bbeae7c6f3e1..9c7963a1ec2dcb3256aa90d1d10bf663045a7354 100644
--- a/python/paddle/fluid/incubate/fleet/collective/__init__.py
+++ b/python/paddle/fluid/incubate/fleet/collective/__init__.py
@@ -151,8 +151,10 @@ class CollectiveOptimizer(DistributedOptimizer):
     """
 
     def __init__(self, optimizer, strategy=DistributedStrategy()):
+        if strategy is None:
+            strategy = DistributedStrategy()
         super(CollectiveOptimizer, self).__init__(optimizer, strategy)
-        if strategy is not None and strategy.forward_recompute:
+        if strategy.forward_recompute:
             self.forward_recompute = True
             self.recompute_checkpoints = strategy.recompute_checkpoints
         else: