diff --git a/SENET/requirement.txt b/SENET/requirement.txt
index 21554873..0e4a92e1 100644
--- a/SENET/requirement.txt
+++ b/SENET/requirement.txt
@@ -35,7 +35,7 @@ msgpack-numpy==0.4.1
 msgpack-python==0.5.4
 multidict==3.3.2
 murmurhash==0.28.0
-nltk==3.2.5
+nltk==3.4.5
 numpy==1.13.3+mkl
 oauth2client==4.1.2
 pathlib==1.0.1
diff --git a/SENET/src/requirement.txt b/SENET/src/requirement.txt
index 21554873..0e4a92e1 100644
--- a/SENET/src/requirement.txt
+++ b/SENET/src/requirement.txt
@@ -35,7 +35,7 @@ msgpack-numpy==0.4.1
 msgpack-python==0.5.4
 multidict==3.3.2
 murmurhash==0.28.0
-nltk==3.2.5
+nltk==3.4.5
 numpy==1.13.3+mkl
 oauth2client==4.1.2
 pathlib==1.0.1