diff --git a/requirements.txt b/requirements.txt
index 6666100..5156309 100644
--- a/requirements.txt
+++ b/requirements.txt
@@ -34,7 +34,7 @@ parso==0.1.1
 pexpect==4.3.1
 pickleshare==0.7.4
 prompt-toolkit==1.0.15
-protobuf==3.5.1
+protobuf==3.15.0
 ptyprocess==0.5.2
 Pygments==2.2.0
 pyparsing==2.2.0