diff --git a/requirements.txt b/requirements.txt
index 3145d5c..318e2bb 100644
--- a/requirements.txt
+++ b/requirements.txt
@@ -41,7 +41,7 @@ pathlib==1.0.1
 pkg-resources==0.0.0
 plac==0.9.6
 preshed==2.0.1
-protobuf==3.6.1
+protobuf==3.15.0
 pydot==1.2.4
 pyparsing==2.2.0
 python-dateutil==2.7.2