diff --git a/docs/requirements.txt b/docs/requirements.txt
index ca0b8dd..1318a88 100644
--- a/docs/requirements.txt
+++ b/docs/requirements.txt
@@ -1,6 +1,6 @@
 alabaster==0.7.9
 argh==0.26.1
-Babel==2.3.4
+Babel==2.9.1
 backports-abc==0.4
 backports.ssl-match-hostname==3.5.0.1
 certifi==2019.3.9