diff --git a/python/paddle/fluid/dygraph/base.py b/python/paddle/fluid/dygraph/base.py
index 0bf620ea2175b58e9a19ffeaa44f6b3f575c3c62..22b95dfd5f2a4b5c6301195121349925d93e67a5 100644
--- a/python/paddle/fluid/dygraph/base.py
+++ b/python/paddle/fluid/dygraph/base.py
@@ -105,8 +105,9 @@ def enable_dygraph(place=None):
             print(fluid.in_dygraph_mode())  # False
     """
     global _functional_dygraph_context_manager
-    _functional_dygraph_context_manager = guard(place=place)
-    _functional_dygraph_context_manager.__enter__()
+    if _functional_dygraph_context_manager is None:
+        _functional_dygraph_context_manager = guard(place=place)
+        _functional_dygraph_context_manager.__enter__()
 
 
 def disable_dygraph():