diff --git a/requirements.txt b/requirements.txt
index 6257e9f..925a772 100644
--- a/requirements.txt
+++ b/requirements.txt
@@ -23,7 +23,7 @@ MarkupSafe==1.0
 oauth2client==3.0.0
 ply==3.8
 proto-google-cloud-datastore-v1==0.90.4
-protobuf==3.3.0
+protobuf==3.15.0
 pyasn1==0.2.3
 pyasn1-modules==0.0.9
 python-firebase-gae==1.0.1