diff --git a/requirements.txt b/requirements.txt
index 0c8387e9..a8f7d130 100644
--- a/requirements.txt
+++ b/requirements.txt
@@ -46,7 +46,7 @@ mock==3.0.5
 murmurhash==1.0.2
 nbconvert==5.5.0
 nbformat==4.4.0
-nltk==3.4.1
+nltk==3.4.5
 notebook==5.7.8
 numpy==1.16.3
 pandas==0.24.2