diff --git a/requirements.txt b/requirements.txt
index 811c4e4..237525d 100644
--- a/requirements.txt
+++ b/requirements.txt
@@ -1,6 +1,6 @@
 flake8
 mock==2.0.0
-protobuf==3.15.0
+protobuf==3.18.3
 pytest==4.3.0
 pytest-cov==2.6.1
 requests==2.21.0