diff --git a/dev_requirements.txt b/dev_requirements.txt
index 3ece45a..a75a8df 100644
--- a/dev_requirements.txt
+++ b/dev_requirements.txt
@@ -1,5 +1,5 @@
 alabaster==0.7.10
-Babel==2.5.1
+Babel==2.9.1
 bumpversion==0.5.3
 certifi==2017.11.5
 chardet==3.0.4