diff --git a/python/examples/imdb/test_py_server.py b/python/examples/imdb/test_py_server.py
index 31d34e19febdae14b9a9c38c0d087e75f8e6843b..f402a0e9d250a6996fb43f40348750d60a1ea4a2 100644
--- a/python/examples/imdb/test_py_server.py
+++ b/python/examples/imdb/test_py_server.py
@@ -13,9 +13,9 @@
 # limitations under the License.
 # pylint: disable=doc-string-missing
 
-from paddle_serving_server.pserving import Op
-from paddle_serving_server.pserving import Channel
-from paddle_serving_server.pserving import PyServer
+from paddle_serving_server.pyserver import Op
+from paddle_serving_server.pyserver import Channel
+from paddle_serving_server.pyserver import PyServer
 
 
 class CNNOp(Op):
diff --git a/python/paddle_serving_server/pyserver.py b/python/paddle_serving_server/pyserver.py
new file mode 100644
index 0000000000000000000000000000000000000000..9102b0a09d32282c5bcf78a86e50db9b8a8e8dd1
--- /dev/null
+++ b/python/paddle_serving_server/pyserver.py
@@ -0,0 +1,213 @@
+# Copyright (c) 2020 PaddlePaddle Authors. All Rights Reserved.
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+# pylint: disable=doc-string-missing
+import threading
+import multiprocessing
+import queue
+import os
+import paddle_serving_server
+from paddle_serving_client import Client
+from concurrent import futures
+import grpc
+import general_python_service_pb2
+import general_python_service_pb2_grpc
+
+
+class Channel(queue.Queue):
+    def __init__(self, consumer=1, maxsize=0, timeout=0, batchsize=1):
+        super(Channel, self).__init__(maxsize=maxsize)
+        self._maxsize = maxsize
+        self._timeout = timeout
+        self._batchsize = batchsize
+        self._consumer = consumer
+        self._pushlock = threading.Lock()
+        self._frontlock = threading.Lock()
+        self._pushbatch = []
+        self._frontbatch = None
+        self._count = 0
+
+    def push(self, item):
+        with self._pushlock:
+            if len(self._pushbatch) == batchsize:
+                self.put(self._pushbatch, timeout=self._timeout)
+                self._pushbatch = []
+            self._pushbatch.append(item)
+
+    def front(self):
+        if consumer == 1:
+            return self.get(timeout=self._timeout)
+        with self._frontlock:
+            if self._count == 0:
+                self._frontbatch = self.get(timeout=self._timeout)
+            self._count += 1
+            if self._count == self._consumer:
+                self._count = 0
+            return self._frontbatch
+
+
+class Op(object):
+    def __init__(self,
+                 inputs,
+                 outputs,
+                 server_model=None,
+                 server_port=None,
+                 device=None,
+                 client_config=None,
+                 server_name=None,
+                 fetch_names=None):
+        self._run = False
+        self.set_inputs(inputs)
+        self.set_outputs(outputs)
+        if client_config is not None and \
+                server_name is not None and \
+                fetch_names is not None:
+            self.set_client(client_config, server_name, fetch_names)
+        self._server_model = server_model
+        self._server_port = server_port
+        self._device = deviceis
+
+    def set_client(self, client_config, server_name, fetch_names):
+        self._client = Client()
+        self._client.load_client_config(client_config)
+        self._client.connect([server_name])
+        self._fetch_names = fetch_names
+
+    def with_serving(self):
+        return self._client is not None
+
+    def get_inputs(self):
+        return self._inputs
+
+    def set_inputs(self, channels):
+        if not isinstance(channels, list):
+            raise TypeError('channels must be list type')
+        self._inputs = channels
+
+    def get_outputs(self):
+        return self._outputs
+
+    def set_outputs(self, channels):
+        if not isinstance(channels, list):
+            raise TypeError('channels must be list type')
+        self._outputs = channels
+
+    def preprocess(self, input_data):
+        return input_data
+
+    def midprocess(self, data):
+        # data = preprocess(input), which is a dict
+        fetch_map = self._client.predict(feed=data, fetch=self._fetch_names)
+        return fetch_map
+
+    def postprocess(self, output_data):
+        return output_data
+
+    def stop(self):
+        self._run = False
+
+    def start(self):
+        self._run = True
+        while self._run:
+            input_data = []
+            for channel in self._inputs:
+                input_data.append(channel.front())
+            data = self.preprocess(input_data)
+
+            if self.with_serving():
+                fetch_map = self.midprocess(data)
+                output_data = self.postprocess(fetch_map)
+            else:
+                output_data = self.postprocess(data)
+
+            for channel in self._outputs:
+                channel.push(output_data)
+
+
+class GeneralPythonService(
+        general_python_service_pb2_grpc.GeneralPythonService):
+    def __init__(self, channel):
+        self._channel = channel
+
+    def Request(self, request, context):
+        pass
+
+    def Response(self, request, context):
+        pass
+
+
+class PyServer(object):
+    def __init__(self):
+        self._channels = []
+        self._ops = []
+        self._op_threads = []
+        self._port = None
+        self._worker_num = None
+
+    def add_channel(self, channel):
+        self._channels.append(channel)
+
+    def add_op(self, op):
+        slef._ops.append(op)
+
+    def gen_desc(self):
+        pass
+
+    def prepare_server(self, port, worker_num):
+        self._port = port
+        self._worker_num = worker_num
+        self.gen_desc()
+
+    def run_server(self):
+        inputs = []
+        outputs = []
+        for op in self._ops:
+            inputs += op.get_inputs()
+            outputs += op.get_outputs()
+            if op.with_serving():
+                self.prepare_serving(op)
+            th = multiprocessing.Process(target=op.start, args=(op, ))
+            th.start()
+            self._op_threads.append(th)
+
+        input_channel = []
+        for channel in inputs:
+            if channel not in outputs:
+                input_channel.append(channel)
+        if len(input_channel) != 1:
+            raise Exception("input_channel more than 1 or no input_channel")
+
+        server = grpc.server(
+            futures.ThreadPoolExecutor(max_workers=self._worker_num))
+        general_python_service_pb2_grpc.add_GeneralPythonService_to_server(
+            GeneralPythonService(input_channel[0]), server)
+        server.start()
+        try:
+            for th in self._op_threads:
+                th.join()
+        except KeyboardInterrupt:
+            server.stop(0)
+
+    def prepare_serving(self, op):
+        model_path = op._server_model
+        port = op._server_port
+        device = op._device
+
+        # run a server (not in PyServing)
+        if device == "cpu":
+            cmd = "python -m paddle_serving_server.serve --model {} --thread 4 --port {} &>/dev/null &".format(
+                model_path, port)
+        else:
+            cmd = "python -m paddle_serving_server_gpu.serve --model {} --thread 4 --port {} &>/dev/null &".format(
+                model_path, port)
+        os.system(cmd)