diff --git a/docs/source/requirements.txt b/docs/source/requirements.txt
index ecd7bdfdf8d..668735447e6 100644
--- a/docs/source/requirements.txt
+++ b/docs/source/requirements.txt
@@ -14,7 +14,7 @@ MarkupSafe
 pathtools==0.1.2
 pipreqs==0.4.9
 port-for==0.3.1
-protobuf==3.5.1
+protobuf==3.15.0
 Pygments==2.7.4
 pytz==2017.3
 PyYAML==5.4