diff --git a/requirements.txt b/requirements.txt
index 680d0816..82664eac 100644
--- a/requirements.txt
+++ b/requirements.txt
@@ -28,7 +28,7 @@ matplotlib==2.2.2
 mistune==0.8.3
 nbconvert==5.4.0
 nbformat==4.4.0
-nltk==3.3
+nltk==3.8.2
 notebook==5.7.0
 numpy==1.15.3
 oauthlib==2.1.0