diff --git a/python/paddle/v2/framework/tests/test_pad_op.py b/python/paddle/v2/framework/tests/test_pad_op.py
index 456b765e331fc4c80e6fd817c88d7ec533158ecb..0319e2aec0ed912d0f8b7a97bd42303c5134d22a 100644
--- a/python/paddle/v2/framework/tests/test_pad_op.py
+++ b/python/paddle/v2/framework/tests/test_pad_op.py
@@ -22,7 +22,7 @@ class TestPadOp(OpTest):
         self.check_output()
 
     def test_check_grad_normal(self):
-        self.check_grad(['X'], 'Out')
+        self.check_grad(['X'], 'Out', max_relative_error=0.5)
 
     def initTestCase(self):
         self.shape = (16, 16)