diff --git a/python/paddle/v2/fluid/tests/test_layers.py b/python/paddle/v2/fluid/tests/test_layers.py
index aea43c2517a02c72c1ee3307afdd3b21910f0064..fa46f86973e82e451d7671d554627359528f5131 100644
--- a/python/paddle/v2/fluid/tests/test_layers.py
+++ b/python/paddle/v2/fluid/tests/test_layers.py
@@ -161,8 +161,8 @@ class TestBook(unittest.TestCase):
                 label=label,
                 chunk_scheme="IOB",
                 num_chunk_types=(label_dict_len - 1) / 2)
-            self.assertNotEqual(crf, None)
-            self.assertNotEqual(crf_decode, None)
+            self.assertFalse(crf is None)
+            self.assertFalse(crf_decode is None)
 
         print(str(program))