diff --git a/requirements_dev.txt b/requirements_dev.txt
index 6999eda..3cc2c39 100644
--- a/requirements_dev.txt
+++ b/requirements_dev.txt
@@ -1,6 +1,6 @@
 alabaster==0.7.8
 astroid==1.4.6
-Babel==2.3.4
+Babel==2.9.1
 certifi==2017.7.27.1
 chardet==3.0.4
 colorama==0.3.7