diff --git a/setup.py b/setup.py
index 91ee24a..8febb2d 100644
--- a/setup.py
+++ b/setup.py
@@ -78,4 +78,5 @@ def build_extension(self, ext):
     cmdclass={'build_ext': custom_build_ext},
     packages=['pyrsistent'],
     package_data={'pyrsistent': ['py.typed', '__init__.pyi', 'typing.pyi']},
+    python_requires='>=3.5',
 )