diff --git a/deepspeech/exps/deepspeech2/bin/test_export.py b/deepspeech/exps/deepspeech2/bin/test_export.py
new file mode 100644
index 00000000..7a012144
--- /dev/null
+++ b/deepspeech/exps/deepspeech2/bin/test_export.py
@@ -0,0 +1,58 @@
+# Copyright (c) 2021 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.
+"""Evaluation for DeepSpeech2 model."""
+from deepspeech.exps.deepspeech2.config import get_cfg_defaults
+from deepspeech.exps.deepspeech2.model import DeepSpeech2ExportTester as ExportTester
+from deepspeech.training.cli import default_argument_parser
+from deepspeech.utils.utility import print_arguments
+
+
+def main_sp(config, args):
+    exp = ExportTester(config, args)
+    exp.setup()
+    exp.run_test()
+
+
+def main(config, args):
+    main_sp(config, args)
+
+
+if __name__ == "__main__":
+    parser = default_argument_parser()
+    # save asr result to
+    parser.add_argument(
+        "--result_file", type=str, help="path of save the asr result")
+    #load jit model from
+    parser.add_argument(
+        "--export_path", type=str, help="path of the jit model to save")
+    parser.add_argument("--model_type")
+    args = parser.parse_args()
+    print_arguments(args, globals())
+    if args.model_type is None:
+        args.model_type = 'offline'
+    print("model_type:{}".format(args.model_type))
+
+    # https://yaml.org/type/float.html
+    config = get_cfg_defaults(args.model_type)
+    if args.config:
+        config.merge_from_file(args.config)
+    if args.opts:
+        config.merge_from_list(args.opts)
+    config.freeze()
+    print(config)
+    if args.dump_config:
+        with open(args.dump_config, 'w') as f:
+            print(config, file=f)
+
+    main(config, args)
diff --git a/deepspeech/exps/deepspeech2/model.py b/deepspeech/exps/deepspeech2/model.py
index 65c905a1..f3e3fcad 100644
--- a/deepspeech/exps/deepspeech2/model.py
+++ b/deepspeech/exps/deepspeech2/model.py
@@ -12,6 +12,7 @@
 # See the License for the specific language governing permissions and
 # limitations under the License.
 """Contains DeepSpeech2 and DeepSpeech2Online model."""
+import os
 import time
 from collections import defaultdict
 from pathlib import Path
@@ -20,6 +21,7 @@ from typing import Optional
 import numpy as np
 import paddle
 from paddle import distributed as dist
+from paddle import inference
 from paddle.io import DataLoader
 from yacs.config import CfgNode
 
@@ -268,24 +270,9 @@ class DeepSpeech2Tester(DeepSpeech2Trainer):
         vocab_list = self.test_loader.collate_fn.vocab_list
 
         target_transcripts = self.ordid2token(texts, texts_len)
-        self.autolog.times.start()
-        self.autolog.times.stamp()
-        result_transcripts = self.model.decode(
-            audio,
-            audio_len,
-            vocab_list,
-            decoding_method=cfg.decoding_method,
-            lang_model_path=cfg.lang_model_path,
-            beam_alpha=cfg.alpha,
-            beam_beta=cfg.beta,
-            beam_size=cfg.beam_size,
-            cutoff_prob=cfg.cutoff_prob,
-            cutoff_top_n=cfg.cutoff_top_n,
-            num_processes=cfg.num_proc_bsearch)
-        self.autolog.times.stamp()
-        self.autolog.times.stamp()
-        self.autolog.times.end()
 
+        result_transcripts = self.compute_result_transcripts(audio, audio_len,
+                                                             vocab_list, cfg)
         for utt, target, result in zip(utts, target_transcripts,
                                        result_transcripts):
             errors, len_ref = errors_func(target, result)
@@ -306,6 +293,26 @@ class DeepSpeech2Tester(DeepSpeech2Trainer):
             error_rate=errors_sum / len_refs,
             error_rate_type=cfg.error_rate_type)
 
+    def compute_result_transcripts(self, audio, audio_len, vocab_list, cfg):
+        self.autolog.times.start()
+        self.autolog.times.stamp()
+        result_transcripts = self.model.decode(
+            audio,
+            audio_len,
+            vocab_list,
+            decoding_method=cfg.decoding_method,
+            lang_model_path=cfg.lang_model_path,
+            beam_alpha=cfg.alpha,
+            beam_beta=cfg.beta,
+            beam_size=cfg.beam_size,
+            cutoff_prob=cfg.cutoff_prob,
+            cutoff_top_n=cfg.cutoff_top_n,
+            num_processes=cfg.num_proc_bsearch)
+        self.autolog.times.stamp()
+        self.autolog.times.stamp()
+        self.autolog.times.end()
+        return result_transcripts
+
     @mp_tools.rank_zero_only
     @paddle.no_grad()
     def test(self):
@@ -395,3 +402,244 @@ class DeepSpeech2Tester(DeepSpeech2Trainer):
             output_dir.mkdir(parents=True, exist_ok=True)
 
         self.output_dir = output_dir
+
+
+class DeepSpeech2ExportTester(DeepSpeech2Tester):
+    def __init__(self, config, args):
+        super().__init__(config, args)
+
+    def compute_result_transcripts(self, audio, audio_len, vocab_list, cfg):
+        if self.args.model_type == "online":
+            output_probs, output_lens = self.static_forward_online(audio,
+                                                                   audio_len)
+        elif self.args.model_type == "offline":
+            output_probs, output_lens = self.static_forward_offline(audio,
+                                                                    audio_len)
+        else:
+            raise Exception("wrong model type")
+
+        self.predictor.clear_intermediate_tensor()
+        self.predictor.try_shrink_memory()
+
+        self.model.decoder.init_decode(cfg.alpha, cfg.beta, cfg.lang_model_path,
+                                       vocab_list, cfg.decoding_method)
+
+        result_transcripts = self.model.decoder.decode_probs(
+            output_probs, output_lens, vocab_list, cfg.decoding_method,
+            cfg.lang_model_path, cfg.alpha, cfg.beta, cfg.beam_size,
+            cfg.cutoff_prob, cfg.cutoff_top_n, cfg.num_proc_bsearch)
+
+        return result_transcripts
+
+    def static_forward_online(self, audio, audio_len,
+                              decoder_chunk_size: int=1):
+        """
+        Parameters
+        ----------
+            audio (Tensor): shape[B, T, D]
+            audio_len (Tensor): shape[B]
+            decoder_chunk_size(int)
+        Returns
+        -------
+            output_probs(numpy.array): shape[B, T, vocab_size]
+            output_lens(numpy.array): shape[B]
+        """
+        output_probs_list = []
+        output_lens_list = []
+        subsampling_rate = self.model.encoder.conv.subsampling_rate
+        receptive_field_length = self.model.encoder.conv.receptive_field_length
+        chunk_stride = subsampling_rate * decoder_chunk_size
+        chunk_size = (decoder_chunk_size - 1
+                      ) * subsampling_rate + receptive_field_length
+
+        x_batch = audio.numpy()
+        batch_size, Tmax, x_dim = x_batch.shape
+        x_len_batch = audio_len.numpy().astype(np.int64)
+        if (Tmax - chunk_size) % chunk_stride != 0:
+            padding_len_batch = chunk_stride - (
+                Tmax - chunk_size
+            ) % chunk_stride  # The length of padding for the batch
+        else:
+            padding_len_batch = 0
+        x_list = np.split(x_batch, batch_size, axis=0)
+        x_len_list = np.split(x_len_batch, batch_size, axis=0)
+
+        for x, x_len in zip(x_list, x_len_list):
+            self.autolog.times.start()
+            self.autolog.times.stamp()
+            x_len = x_len[0]
+            assert (chunk_size <= x_len)
+
+            if (x_len - chunk_size) % chunk_stride != 0:
+                padding_len_x = chunk_stride - (x_len - chunk_size
+                                                ) % chunk_stride
+            else:
+                padding_len_x = 0
+
+            padding = np.zeros(
+                (x.shape[0], padding_len_x, x.shape[2]), dtype=x.dtype)
+            padded_x = np.concatenate([x, padding], axis=1)
+
+            num_chunk = (x_len + padding_len_x - chunk_size) / chunk_stride + 1
+            num_chunk = int(num_chunk)
+
+            chunk_state_h_box = np.zeros(
+                (self.config.model.num_rnn_layers, 1,
+                 self.config.model.rnn_layer_size),
+                dtype=x.dtype)
+            chunk_state_c_box = np.zeros(
+                (self.config.model.num_rnn_layers, 1,
+                 self.config.model.rnn_layer_size),
+                dtype=x.dtype)
+
+            input_names = self.predictor.get_input_names()
+            audio_handle = self.predictor.get_input_handle(input_names[0])
+            audio_len_handle = self.predictor.get_input_handle(input_names[1])
+            h_box_handle = self.predictor.get_input_handle(input_names[2])
+            c_box_handle = self.predictor.get_input_handle(input_names[3])
+
+            probs_chunk_list = []
+            probs_chunk_lens_list = []
+            for i in range(0, num_chunk):
+                start = i * chunk_stride
+                end = start + chunk_size
+                x_chunk = padded_x[:, start:end, :]
+                if x_len < i * chunk_stride:
+                    x_chunk_lens = 0
+                else:
+                    x_chunk_lens = min(x_len - i * chunk_stride, chunk_size)
+
+                if (x_chunk_lens <
+                        receptive_field_length):  #means the number of input frames in the chunk is not enough for predicting one prob
+                    break
+                x_chunk_lens = np.array([x_chunk_lens])
+                audio_handle.reshape(x_chunk.shape)
+                audio_handle.copy_from_cpu(x_chunk)
+
+                audio_len_handle.reshape(x_chunk_lens.shape)
+                audio_len_handle.copy_from_cpu(x_chunk_lens)
+
+                h_box_handle.reshape(chunk_state_h_box.shape)
+                h_box_handle.copy_from_cpu(chunk_state_h_box)
+
+                c_box_handle.reshape(chunk_state_c_box.shape)
+                c_box_handle.copy_from_cpu(chunk_state_c_box)
+
+                output_names = self.predictor.get_output_names()
+                output_handle = self.predictor.get_output_handle(
+                    output_names[0])
+                output_lens_handle = self.predictor.get_output_handle(
+                    output_names[1])
+                output_state_h_handle = self.predictor.get_output_handle(
+                    output_names[2])
+                output_state_c_handle = self.predictor.get_output_handle(
+                    output_names[3])
+                self.predictor.run()
+                output_chunk_probs = output_handle.copy_to_cpu()
+                output_chunk_lens = output_lens_handle.copy_to_cpu()
+                chunk_state_h_box = output_state_h_handle.copy_to_cpu()
+                chunk_state_c_box = output_state_c_handle.copy_to_cpu()
+
+                probs_chunk_list.append(output_chunk_probs)
+                probs_chunk_lens_list.append(output_chunk_lens)
+            output_probs = np.concatenate(probs_chunk_list, axis=1)
+            output_lens = np.sum(probs_chunk_lens_list, axis=0)
+            vocab_size = output_probs.shape[2]
+            output_probs_padding_len = Tmax + padding_len_batch - output_probs.shape[
+                1]
+            output_probs_padding = np.zeros(
+                (1, output_probs_padding_len, vocab_size),
+                dtype=output_probs.
+                dtype)  # The prob padding for a piece of utterance
+            output_probs = np.concatenate(
+                [output_probs, output_probs_padding], axis=1)
+            output_probs_list.append(output_probs)
+            output_lens_list.append(output_lens)
+            self.autolog.times.stamp()
+            self.autolog.times.stamp()
+            self.autolog.times.end()
+        output_probs = np.concatenate(output_probs_list, axis=0)
+        output_lens = np.concatenate(output_lens_list, axis=0)
+        return output_probs, output_lens
+
+    def static_forward_offline(self, audio, audio_len):
+        """
+        Parameters
+        ----------
+            audio (Tensor): shape[B, T, D]
+            audio_len (Tensor): shape[B]
+
+        Returns
+        -------
+            output_probs(numpy.array): shape[B, T, vocab_size]
+            output_lens(numpy.array): shape[B]
+        """
+        x = audio.numpy()
+        x_len = audio_len.numpy().astype(np.int64)
+
+        input_names = self.predictor.get_input_names()
+        audio_handle = self.predictor.get_input_handle(input_names[0])
+        audio_len_handle = self.predictor.get_input_handle(input_names[1])
+
+        audio_handle.reshape(x.shape)
+        audio_handle.copy_from_cpu(x)
+
+        audio_len_handle.reshape(x_len.shape)
+        audio_len_handle.copy_from_cpu(x_len)
+
+        self.autolog.times.start()
+        self.autolog.times.stamp()
+        self.predictor.run()
+        self.autolog.times.stamp()
+        self.autolog.times.stamp()
+        self.autolog.times.end()
+
+        output_names = self.predictor.get_output_names()
+        output_handle = self.predictor.get_output_handle(output_names[0])
+        output_lens_handle = self.predictor.get_output_handle(output_names[1])
+        output_probs = output_handle.copy_to_cpu()
+        output_lens = output_lens_handle.copy_to_cpu()
+        return output_probs, output_lens
+
+    def run_test(self):
+        try:
+            self.test()
+        except KeyboardInterrupt:
+            exit(-1)
+
+    def setup(self):
+        """Setup the experiment.
+        """
+        paddle.set_device(self.args.device)
+
+        self.setup_output_dir()
+
+        self.setup_dataloader()
+        self.setup_model()
+
+        self.iteration = 0
+        self.epoch = 0
+
+    def setup_output_dir(self):
+        """Create a directory used for output.
+        """
+        # output dir
+        if self.args.output:
+            output_dir = Path(self.args.output).expanduser()
+            output_dir.mkdir(parents=True, exist_ok=True)
+        else:
+            output_dir = Path(self.args.export_path).expanduser().parent.parent
+            output_dir.mkdir(parents=True, exist_ok=True)
+
+        self.output_dir = output_dir
+
+    def setup_model(self):
+        super().setup_model()
+        speedyspeech_config = inference.Config(
+            self.args.export_path + ".pdmodel",
+            self.args.export_path + ".pdiparams")
+        if (os.environ['CUDA_VISIBLE_DEVICES'].strip() != ''):
+            speedyspeech_config.enable_use_gpu(100, 0)
+            speedyspeech_config.enable_memory_optim()
+        speedyspeech_predictor = inference.create_predictor(speedyspeech_config)
+        self.predictor = speedyspeech_predictor
diff --git a/deepspeech/models/ds2/deepspeech2.py b/deepspeech/models/ds2/deepspeech2.py
index 1ffd797b..5f8f3255 100644
--- a/deepspeech/models/ds2/deepspeech2.py
+++ b/deepspeech/models/ds2/deepspeech2.py
@@ -280,7 +280,7 @@ class DeepSpeech2InferModel(DeepSpeech2Model):
         """
         eouts, eouts_len = self.encoder(audio, audio_len)
         probs = self.decoder.softmax(eouts)
-        return probs
+        return probs, eouts_len
 
     def export(self):
         static_model = paddle.jit.to_static(
diff --git a/deepspeech/models/ds2_online/deepspeech2.py b/deepspeech/models/ds2_online/deepspeech2.py
index 5ef4431a..f597a578 100644
--- a/deepspeech/models/ds2_online/deepspeech2.py
+++ b/deepspeech/models/ds2_online/deepspeech2.py
@@ -100,12 +100,12 @@ class CRNNEncoder(nn.Layer):
         """Compute Encoder outputs
 
         Args:
-            x (Tensor): [B, feature_size, D]
+            x (Tensor): [B, T, D]
             x_lens (Tensor): [B]
             init_state_h_box(Tensor): init_states h for RNN layers: [num_rnn_layers * num_directions, batch_size, hidden_size]
             init_state_c_box(Tensor): init_states c for RNN layers: [num_rnn_layers * num_directions, batch_size, hidden_size]
         Return:
-            x (Tensor): encoder outputs, [B, size, D]
+            x (Tensor): encoder outputs, [B, T, D]
             x_lens (Tensor): encoder length, [B]
             final_state_h_box(Tensor): final_states h for RNN layers: [num_rnn_layers * num_directions, batch_size, hidden_size]
             final_state_c_box(Tensor): final_states c for RNN layers: [num_rnn_layers * num_directions, batch_size, hidden_size]
diff --git a/examples/aishell/s0/local/test_export.sh b/examples/aishell/s0/local/test_export.sh
new file mode 100755
index 00000000..b6d58097
--- /dev/null
+++ b/examples/aishell/s0/local/test_export.sh
@@ -0,0 +1,39 @@
+#!/bin/bash
+
+if [ $# != 3 ];then
+    echo "usage: ${0} config_path ckpt_path_prefix model_type"
+    exit -1
+fi
+
+ngpu=$(echo $CUDA_VISIBLE_DEVICES | awk -F "," '{print NF}')
+echo "using $ngpu gpus..."
+
+device=gpu
+if [ ${ngpu} == 0 ];then
+    device=cpu
+fi
+config_path=$1
+jit_model_export_path=$2
+model_type=$3
+
+# download language model
+bash local/download_lm_ch.sh
+if [ $? -ne 0 ]; then
+   exit 1
+fi
+
+python3 -u ${BIN_DIR}/test_export.py \
+--device ${device} \
+--nproc 1 \
+--config ${config_path} \
+--result_file ${jit_model_export_path}.rsl \
+--export_path ${jit_model_export_path} \
+--model_type ${model_type}
+
+if [ $? -ne 0 ]; then
+    echo "Failed in evaluation!"
+    exit 1
+fi
+
+
+exit 0
diff --git a/examples/aishell/s0/run.sh b/examples/aishell/s0/run.sh
index 7cd63999..e5ab12a5 100755
--- a/examples/aishell/s0/run.sh
+++ b/examples/aishell/s0/run.sh
@@ -39,3 +39,8 @@ if [ ${stage} -le 4 ] && [ ${stop_stage} -ge 4 ]; then
     # export ckpt avg_n
     CUDA_VISIBLE_DEVICES=0 ./local/export.sh ${conf_path} exp/${ckpt}/checkpoints/${avg_ckpt} exp/${ckpt}/checkpoints/${avg_ckpt}.jit ${model_type}
 fi
+
+if [ ${stage} -le 5 ] && [ ${stop_stage} -ge 5 ]; then
+    # test export ckpt avg_n
+    CUDA_VISIBLE_DEVICES=0 ./local/test_export.sh ${conf_path} exp/${ckpt}/checkpoints/${avg_ckpt}.jit ${model_type}|| exit -1
+fi