diff --git a/docker_requirements.txt b/docker_requirements.txt
index fc6b7947b..d23607aa8 100644
--- a/docker_requirements.txt
+++ b/docker_requirements.txt
@@ -12,7 +12,7 @@ gensim==4.3.2
 h5py==3.1.0
 khanaa==0.0.6
 nlpo3==1.3.0
-nltk==3.6.6
+nltk==3.9
 numpy==1.22.*
 OSKut==1.3
 pandas==1.4.*