diff --git a/python/paddle/fluid/data.py b/python/paddle/fluid/data.py
index b90a681ed8e1bb3de0e4a9825a5af17eb0eaf457..008765c3f53ad158d999d01c6a632e81e55d914e 100644
--- a/python/paddle/fluid/data.py
+++ b/python/paddle/fluid/data.py
@@ -13,6 +13,7 @@
 # limitations under the License.
 
 import numpy as np
+import six
 
 from . import core
 from .layer_helper import LayerHelper
@@ -86,6 +87,11 @@ def data(name, shape, dtype='float32', lod_level=0):
 
     """
     helper = LayerHelper('data', **locals())
+    shape = list(shape)
+    for i in six.moves.range(len(shape)):
+        if shape[i] is None:
+            shape[i] = -1
+
     return helper.create_global_variable(
         name=name,
         shape=shape,
diff --git a/python/paddle/fluid/tests/unittests/test_feed_data_check_shape_type.py b/python/paddle/fluid/tests/unittests/test_feed_data_check_shape_type.py
index 2489ae8e266df95d8b96d2dcb608cff5d2764338..9f70c63c69d5f42c4d23285a3e5e5bdb96fb20e7 100644
--- a/python/paddle/fluid/tests/unittests/test_feed_data_check_shape_type.py
+++ b/python/paddle/fluid/tests/unittests/test_feed_data_check_shape_type.py
@@ -83,7 +83,7 @@ class TestFeedData(unittest.TestCase):
 
     def _test_feed_data_shape_mismatch(self, use_cuda, use_parallel_executor):
         batch_size = self._get_batch_size(use_cuda, use_parallel_executor)
-        in_size = [-1, 3, 4, 8]
+        in_size = [None, 3, 4, 8]
         feed_in_data = np.random.uniform(
             size=[batch_size, 3, 4, 5]).astype(np.float32)
         label_size = [-1, 1]
@@ -97,7 +97,7 @@ class TestFeedData(unittest.TestCase):
         in_size = [-1, 3, 4, 5]
         feed_in_data = np.random.uniform(
             size=[batch_size, 3, 4, 5]).astype(np.float32)
-        label_size = (-1, 1)
+        label_size = (None, 1)
         feed_label = np.random.randint(
             low=0, high=self.class_num, size=[batch_size, 1]).astype(np.int64)
         self._feed_data_in_executor(in_size, label_size, feed_in_data,