diff --git a/setup.py b/setup.py
index b3c7ec689..91b996254 100644
--- a/setup.py
+++ b/setup.py
@@ -1962,6 +1962,7 @@ def convert_optional_data_files(files):
     long_description_content_type="text/markdown",
     author="Mark Hammond (et al)",
     author_email="mhammond@skippinet.com.au",
+    python_requires=">=3.9",
     project_urls={
         # https://docs.pypi.org/project_metadata/#general-url
         "Homepage": "https://github.com/mhammond/pywin32",