diff --git a/python/examples/bert/prepare_model.py b/python/examples/bert/prepare_model.py
index b5f80a78feb07a0617bec3833bbe1cf3884d7dea..5a7c5893d9dfc9473c5fabb8f111f6798a6a20d3 100644
--- a/python/examples/bert/prepare_model.py
+++ b/python/examples/bert/prepare_model.py
@@ -14,11 +14,12 @@
 
 import paddlehub as hub
 import paddle.fluid as fluid
+import sys
 import paddle_serving_client.io as serving_io
 
 model_name = "bert_chinese_L-12_H-768_A-12"
 module = hub.Module(model_name)
-inputs, outputs, program = module.context(trainable=True, max_seq_len=20)
+inputs, outputs, program = module.context(trainable=True, max_seq_len=int(sys.argv[1]))
 place = fluid.core_avx.CPUPlace()
 exe = fluid.Executor(place)
 input_ids = inputs["input_ids"]
@@ -34,7 +35,7 @@ feed_var_names = [
 
 target_vars = [pooled_output, sequence_output]
 
-serving_io.save_model("serving_server_model", "serving_client_conf", {
+serving_io.save_model("bert_seq{}_model".format(sys.argv[1]), "bert_seq{}_client".format(sys.argv[1]), {
     "input_ids": input_ids,
     "position_ids": position_ids,
     "segment_ids": segment_ids,
diff --git a/python/paddle_serving_server/web_service.py b/python/paddle_serving_server/web_service.py
index 00c060f1b207a2de3f45a46483819ef4ff9aa5c9..d54dc7765656f726397a6553498b4d6da72e59dd 100755
--- a/python/paddle_serving_server/web_service.py
+++ b/python/paddle_serving_server/web_service.py
@@ -60,6 +60,8 @@ class WebService(object):
             if "fetch" not in request.json:
                 abort(400)
             feed, fetch = self.preprocess(request.json, request.json["fetch"])
+            if "fetch" in feed:
+                del feed["fetch"]
             fetch_map = client_service.predict(feed=feed, fetch=fetch)
             fetch_map = self.postprocess(feed=request.json, fetch=fetch, fetch_map=fetch_map)
             return fetch_map