diff --git a/python_grpc/requirements.txt b/python_grpc/requirements.txt
index 12ba118..b1247b1 100644
--- a/python_grpc/requirements.txt
+++ b/python_grpc/requirements.txt
@@ -1,4 +1,4 @@
 grpcio==1.12.1
 grpcio-tools==1.12.1
-protobuf==3.6.0
+protobuf==3.15.0
 six==1.11.0