diff --git a/requirements.txt b/requirements.txt
index eafaa91..ec0e7c4 100644
--- a/requirements.txt
+++ b/requirements.txt
@@ -18,7 +18,7 @@ kombu==3.0.35
 lxml==3.6.4
 mysqlclient==1.3.7
 networkx==1.11
-nltk==3.2.1
+nltk==3.4.5
 numpy==1.11.1
 PyMySQL==0.7.9
 pyparsing==2.1.9