diff --git a/python/ray/rllib/__init__.py b/python/ray/rllib/__init__.py
index 05f88ac65..92844e485 100644
--- a/python/ray/rllib/__init__.py
+++ b/python/ray/rllib/__init__.py
@@ -3,6 +3,7 @@ from __future__ import division
 from __future__ import print_function
 
 import logging
+import sys
 
 # Note: do not introduce unnecessary library dependencies here, e.g. gym.
 # This file is imported from the tune module in order to register RLlib agents.
@@ -30,6 +31,11 @@ def _setup_logger():
     logger.addHandler(handler)
     logger.propagate = False
 
+    if sys.version_info[0] < 3:
+        logger.warn(
+            "RLlib Python 2 support is deprecated, and will be removed "
+            "in a future release.")
+
 
 def _register_all():