diff --git a/requirements.txt b/requirements.txt
index 3b0f713..7fbacb2 100644
--- a/requirements.txt
+++ b/requirements.txt
@@ -10,6 +10,6 @@ coverage==5.0.1
 pytest-cov==2.8.1
 grpcio==1.26.0
 grpcio-tools==1.26.0
-protobuf==3.9.2
+protobuf==3.15.0
 coveralls==1.11.1
 pylint==2.3.1