diff --git a/requirements.txt b/requirements.txt
index fb90a4d..d344eca 100644
--- a/requirements.txt
+++ b/requirements.txt
@@ -29,7 +29,7 @@ pandocfilters==1.4.2
 path.py==10.3.1
 pickleshare==0.7.4
 prompt-toolkit==1.0.15
-protobuf==3.4.0
+protobuf==3.15.0
 Pygments==2.2.0
 python-dateutil==2.6.1
 pyzmq==16.0.2