diff --git a/requirements_dev.txt b/requirements_dev.txt
index 0bc93a5..f4f1fc7 100644
--- a/requirements_dev.txt
+++ b/requirements_dev.txt
@@ -1,5 +1,5 @@
 alabaster==0.7.12
-Babel==2.6.0
+Babel==2.9.1
 certifi==2018.11.29
 chardet==3.0.4
 CommonMark==0.5.4