diff --git a/python/requirements.txt b/python/requirements.txt
index e7fc6cd651cb0f7f8a8907fade9177fd8bb17f4b..08ee782bb8de7e239a58cb85c33e51451206d3e4 100644
--- a/python/requirements.txt
+++ b/python/requirements.txt
@@ -1,6 +1,6 @@
 requests>=2.20.0
 numpy>=1.13
-protobuf>=3.1.0
+protobuf>=3.1.0, <=3.20.0
 Pillow
 six
 decorator