diff --git a/setup.py b/setup.py
index 87733be..0c57763 100644
--- a/setup.py
+++ b/setup.py
@@ -13,7 +13,7 @@
     license = f.read()
 
 INSTALL_REQUIRES = (
-    'protobuf==3.11.3',
+    'protobuf==3.15.0',
     'grpcio==1.27.1',
     'grpcio-tools==1.27.1',
     'googleapis-common-protos==1.51.0',