diff --git a/requirements.txt b/requirements.txt
index 5f93270..c64c3ba 100644
--- a/requirements.txt
+++ b/requirements.txt
@@ -1,5 +1,5 @@
 alabaster==0.7.10
-Babel==2.5.0
+Babel==2.9.1
 certifi==2017.7.27.1
 chardet==3.0.4
 docutils==0.14