diff --git a/docs/requirements.txt b/docs/requirements.txt
index 7e7bd07..3250d76 100644
--- a/docs/requirements.txt
+++ b/docs/requirements.txt
@@ -1,5 +1,5 @@
 alabaster==0.7.12
-Babel==2.7.0
+Babel==2.9.1
 breathe==4.13.0.post0
 certifi==2019.3.9
 chardet==3.0.4