diff --git a/setup.py b/setup.py
index a56e92ddfab..1d5798997ad 100644
--- a/setup.py
+++ b/setup.py
@@ -68,7 +68,7 @@ def package_files(directory):
         "ansicolors==1.1.8",
         "async-exit-stack; python_version < '3.7'",
         "async-generator",
-        "beartype >= 0.9.1",
+        "beartype >= 0.9.1, < 0.10.0",
         "cloudevents",
         "cloudpickle",
         "tqdm>=4.62.0",