diff --git a/python/paddle/v2/fluid/tests/test_maxout_op.py b/python/paddle/v2/fluid/tests/test_maxout_op.py
index 1416e13feb9371ca7ebe28af5c33a99d493858b9..05e42f315833cab5bc5272cbd2173ea8012ff7f5 100644
--- a/python/paddle/v2/fluid/tests/test_maxout_op.py
+++ b/python/paddle/v2/fluid/tests/test_maxout_op.py
@@ -14,8 +14,7 @@ class TestMaxOutOp(OpTest):
         self.op_type = "maxout"
         self.init_test_case()
         input = np.random.random(self.shape).astype("float32")
-        output = self.MaxOut_forward_naive(input, self.groups,
-                self.num_channels).astype("float32")
+        output = self.MaxOut_forward_naive(input, self.groups).astype("float32")
 
         self.inputs = {'X': input}
         self.attrs = {'groups': self.groups}