diff --git a/python/paddle_serving_server/pyserver.py b/python/paddle_serving_server/pyserver.py
index 8dda9a68e560df67d717024ef5cb905f3893afa8..dfe6d73dfabe710859332ca86523c4ab54d1747b 100644
--- a/python/paddle_serving_server/pyserver.py
+++ b/python/paddle_serving_server/pyserver.py
@@ -87,6 +87,7 @@ class ChannelDataType(enum.Enum):
     CHANNEL_PBDATA = 0
     CHANNEL_FUTURE = 1
     CHANNEL_NPDATA = 2
+    ERROR = 3
 
 
 class ChannelData(object):
@@ -116,6 +117,7 @@ class ChannelData(object):
             pbdata.ecode = ecode
             pbdata.id = data_id
             pbdata.error_info = error_info
+            datatype = ChannelDataType.ERROR.value
         else:
             if datatype == ChannelDataType.CHANNEL_FUTURE.value:
                 if pbdata is None:
@@ -136,7 +138,7 @@ class ChannelData(object):
                         pbdata.error_info = error_info
                         logging.error(pbdata.error_info)
                     else:
-                        for name, value in postped_data.items():
+                        for name, value in npdata.items():
                             inst = channel_pb2.Inst()
                             inst.data = value.tobytes()
                             inst.name = name