diff --git a/requirements.txt b/requirements.txt
index 4bf9985..0dd5f3f 100644
--- a/requirements.txt
+++ b/requirements.txt
@@ -18,7 +18,7 @@ numpy==1.17.1
 opt-einsum==3.0.1
 Pillow==6.1.0
 promise==2.2.1
-protobuf==3.9.1
+protobuf==3.18.3
 psutil==5.6.3
 requests==2.22.0
 six==1.12.0