diff --git a/requirements.txt b/requirements.txt
index 23a374c..edb9cf3 100644
--- a/requirements.txt
+++ b/requirements.txt
@@ -42,7 +42,7 @@ google-cloud-bigquery==1.5.1
 google-cloud-core==0.28.1
 google-resumable-media==0.3.1
 googleapis-common-protos==1.5.3
-protobuf==3.6.1
+protobuf==3.15.0
 requests==2.20.0
 setuptools==40.4.3
 urllib3==1.24.2