diff --git a/setup.py b/setup.py
deleted file mode 100644
index 57a5a943dc..0000000000
--- a/setup.py
+++ /dev/null
@@ -1,21 +0,0 @@
-import sys
-
-from setuptools import setup
-
-sys.stderr.write(
-    """
-===============================
-Unsupported installation method
-===============================
-ruff no longer supports installation with `python setup.py install`.
-Please use `python -m pip install .` instead.
-""",
-)
-sys.exit(1)
-
-# The below code will never execute, however GitHub is particularly
-# picky about where it finds Python packaging metadata.
-# See: https://github.com/github/feedback/discussions/6456
-#
-# To be removed once GitHub catches up.
-setup(name="ruff", install_requires=[])