diff --git a/requirements.txt b/requirements.txt
index faedf6c..58b2a35 100644
--- a/requirements.txt
+++ b/requirements.txt
@@ -40,7 +40,7 @@ numpy==1.16.4
 numpydoc==0.9.1
 pandas==0.24.2
 pandocfilters==1.4.2
-protobuf==3.9.0
+protobuf==3.15.0
 requests==2.22.0
 retrying==1.3.3
 scikit-image==0.15.0