diff --git a/requirements.txt b/requirements.txt
index 94c5312..75e9856 100644
--- a/requirements.txt
+++ b/requirements.txt
@@ -16,7 +16,7 @@ kiwisolver==1.0.1
 Markdown==3.0.1
 matplotlib==3.0.2
 numpy==1.15.4
-protobuf==3.6.1
+protobuf==3.15.0
 pyparsing==2.3.0
 python-datamuse==1.2.1
 python-dateutil==2.7.5