diff --git a/docs/requirements.txt b/docs/requirements.txt
index a8c1ea3c..9942d571 100644
--- a/docs/requirements.txt
+++ b/docs/requirements.txt
@@ -2,7 +2,7 @@ alabaster==0.7.12
 appnope==0.1.0
 asn1crypto==0.22.0
 astroid==1.5.3
-Babel==2.6.0
+Babel==2.9.1
 bleach==2.1.1
 certifi==2018.4.16
 cffi==1.10.0