diff --git a/setup.py b/setup.py
index 49bb1034..3c40548d 100644
--- a/setup.py
+++ b/setup.py
@@ -30,7 +30,7 @@
 release_status = "Development Status :: 5 - Production/Stable"
 dependencies = [
     "googleapis-common-protos >= 1.56.2, < 2.0dev",
-    "protobuf >= 3.15.0, <4.0.0dev",
+    "protobuf >= 3.15.0, <5.0.0dev",
     "google-auth >= 1.25.0, < 3.0dev",
     "requests >= 2.18.0, < 3.0.0dev",
 ]