diff --git a/setup.py b/setup.py
index f7ab791..3553aa4 100644
--- a/setup.py
+++ b/setup.py
@@ -27,6 +27,7 @@
         "Programming Language :: Python :: 3.6",
         "Programming Language :: Python :: 3.7",
     ],
+    python_requires=">=3.5,<4",
     description="Python domain model classes for the MythX platform",
     install_requires=requirements,
     license="MIT license",