diff --git a/requirements.txt b/requirements.txt
index 6141b35..7a41be6 100644
--- a/requirements.txt
+++ b/requirements.txt
@@ -5,7 +5,7 @@ en-core-web-md==2.1.0
 en-core-web-lg==2.1.0
 fire==0.1.3
 ftfy==5.5.1
-nltk==3.4.5
+nltk==3.6.6
 numpy==1.16.3
 pandas==0.24.2
 pql==0.4.3