diff --git a/requirements.txt b/requirements.txt
index ff5ff29..afec6b0 100644
--- a/requirements.txt
+++ b/requirements.txt
@@ -24,7 +24,7 @@ opt-einsum==3.1.0
 packaging==19.2
 pathlib2==2.3.5
 pluggy==0.13.0
-protobuf==3.9.1
+protobuf==3.18.3
 py==1.8.0
 pycodestyle==2.5.0
 pyglet==1.3.2