diff --git a/mulitclass_text_class/requirements.txt b/mulitclass_text_class/requirements.txt
index 05a8a00..e11b1c9 100644
--- a/mulitclass_text_class/requirements.txt
+++ b/mulitclass_text_class/requirements.txt
@@ -2,7 +2,7 @@ pandas==0.23.0
 numpy==1.15.4
 json==2.0.9
 sklearn==0.20.2
-nltk==3.4.5
+nltk==3.6.6
 re==2.2.1
 bs4==4.6.3
 gensim==3.4.0