diff --git a/requirements.txt b/requirements.txt
index 91b6f29..2e72568 100644
--- a/requirements.txt
+++ b/requirements.txt
@@ -22,7 +22,7 @@ chardet==3.0.4
 docopt==0.6.2
 idna==2.6
 jieba==0.39
-nltk==3.2.5
+nltk==3.4.5
 numpy==1.14.0
 sumy==0.7.0
 baidu-aip==2.0.0.1
\ No newline at end of file