diff --git a/requirements.txt b/requirements.txt
index bc50c45..de3d7a8 100644
--- a/requirements.txt
+++ b/requirements.txt
@@ -1,4 +1,4 @@
-nltk==3.4
+nltk==3.4.5
 numpy==1.15.4
 singledispatch==3.4.0.3
 six==1.12.0