diff --git a/python/paddle/fluid/contrib/layers/metric_op.py b/python/paddle/fluid/contrib/layers/metric_op.py
index d913df7d69a6c4256a9030d4cc79b9cc1a6732d6..a2b23167dc322cbf5b1b877a78d961ed4c4fc3de 100755
--- a/python/paddle/fluid/contrib/layers/metric_op.py
+++ b/python/paddle/fluid/contrib/layers/metric_op.py
@@ -16,6 +16,7 @@ Contrib layers just related to metric.
 """
 
 import warnings
+import paddle
 from paddle.fluid.layer_helper import LayerHelper
 from paddle.fluid.framework import Variable
 from paddle.fluid.param_attr import ParamAttr