diff --git a/mpeds/requirements.txt b/mpeds/requirements.txt
index 25dd41e..2bfa76e 100644
--- a/mpeds/requirements.txt
+++ b/mpeds/requirements.txt
@@ -1,5 +1,5 @@
 pandas==0.20.1
 numpy==1.12.1
-nltk==3.2
+nltk==3.4.5
 scikit-learn==0.18.1
 scipy==0.19.0