diff --git a/requirements.txt b/requirements.txt
index 5c2ddfb..d46485b 100644
--- a/requirements.txt
+++ b/requirements.txt
@@ -25,7 +25,7 @@ numpy==1.18.4
 opt-einsum==3.2.1
 pathspec==0.8.0
 Pillow==7.1.2
-protobuf==3.11.3
+protobuf==3.15.0
 pycodestyle==2.6.0
 pyflakes==2.2.0
 pyparsing==2.4.7