diff --git a/examples/sequence_tagging/README.md b/examples/sequence_tagging/README.md
index 898f3abbcbc6bbee447b258c554ef4cde98143e4..b36e9cda77efe701dcc1e342e65f50c70fd69c8d 100644
--- a/examples/sequence_tagging/README.md
+++ b/examples/sequence_tagging/README.md
@@ -14,7 +14,7 @@ Sequence Tagging，是一个序列标注模型，模型可用于实现，分词
 
 #### 1.PaddlePaddle 安装
 
-本项目依赖 PaddlePaddle 1.7 及以上版本和PaddleHub 1.0.0及以上版本 ，PaddlePaddle安装请参考官网 [快速安装](http://www.paddlepaddle.org/paddle#quick-start)，PaddleHub安装参考 [PaddleHub](https://github.com/PaddlePaddle/PaddleHub)。
+本项目依赖 PaddlePaddle 1.8 及以上版本和PaddleHub 1.0.0及以上版本 ，PaddlePaddle安装请参考官网 [快速安装](http://www.paddlepaddle.org/paddle#quick-start)，PaddleHub安装参考 [PaddleHub](https://github.com/PaddlePaddle/PaddleHub)。
 
 > Warning: GPU 和 CPU 版本的 PaddlePaddle 分别是 paddlepaddle-gpu 和 paddlepaddle，请安装时注意区别。
 
diff --git a/examples/sequence_tagging/predict.py b/examples/sequence_tagging/predict.py
index bcb39265d7ef8a08ce6700d599b37a4f4ae19054..5067eb7c844972dd2a625901e841196b527c6e8a 100644
--- a/examples/sequence_tagging/predict.py
+++ b/examples/sequence_tagging/predict.py
@@ -21,6 +21,7 @@ from __future__ import print_function
 import io
 import os
 import sys
+import six
 import math
 import argparse
 import numpy as np
@@ -71,7 +72,12 @@ def main(args):
             word_len = length[i]
             word_ids = results[i][:word_len]
             tags = [dataset.id2label_dict[str(id)] for id in word_ids]
-            f.write("\002".join(tags) + "\n")
+            if six.PY3:
+                tags = [bytes(tag, encoding="utf8") for tag in tags]
+                out = b"\002".join(tags) + b"\n"
+                f.write(out)
+            else:
+                f.write("\002".join(tags) + "\n")
 
 
 if __name__ == '__main__':
diff --git a/examples/sequence_tagging/reader.py b/examples/sequence_tagging/reader.py
index 7a772b3fbbc80478dfc4e9096273a60ade05c79a..991a24e867c5d171247a1497f744cb96d0758f8b 100644
--- a/examples/sequence_tagging/reader.py
+++ b/examples/sequence_tagging/reader.py
@@ -20,7 +20,6 @@ from __future__ import print_function
 
 import io
 import os
-import leveldb
 import numpy as np
 import shutil
 from functools import partial