diff --git a/requirements.txt b/requirements.txt
index b0880c4..b9c5940 100644
--- a/requirements.txt
+++ b/requirements.txt
@@ -1,6 +1,6 @@
 Cython==0.29.23
 h5py==2.10.0
-nltk==3.6.1
+nltk==3.6.5
 nose==1.3.7
 numpy==1.20.1
 pandas==1.2.4