diff --git a/requirements.txt b/requirements.txt
index e821576..4b3db51 100644
--- a/requirements.txt
+++ b/requirements.txt
@@ -1,2 +1,2 @@
 grpcio==1.16.0
-protobuf==3.6.1
+protobuf==3.15.0
diff --git a/tests/requirements.txt b/tests/requirements.txt
index e821576..4b3db51 100644
--- a/tests/requirements.txt
+++ b/tests/requirements.txt
@@ -1,2 +1,2 @@
 grpcio==1.16.0
-protobuf==3.6.1
+protobuf==3.15.0