diff --git a/requirements.txt b/requirements.txt
index 289297a..399aeda 100644
--- a/requirements.txt
+++ b/requirements.txt
@@ -1,4 +1,4 @@
 grpcio==1.22.0
 grpcio-tools==1.22.0
-protobuf==3.9.0
+protobuf==3.15.0
 six==1.12.0