diff --git a/gunicorn/workers/__init__.py b/gunicorn/workers/__init__.py
index 43ddc9db..d580387b 100644
--- a/gunicorn/workers/__init__.py
+++ b/gunicorn/workers/__init__.py
@@ -3,13 +3,18 @@
 # This file is part of gunicorn released under the MIT license.
 # See the NOTICE for more information.
 
+import sys
+
 # supported gunicorn workers.
 SUPPORTED_WORKERS={
         "sync": "gunicorn.workers.sync.SyncWorker",
         "eventlet": "gunicorn.workers.geventlet.EventletWorker",
-        "gaiohttp": "gunicorn.workers.gaiohttp.AiohttpWorker",
         "gevent": "gunicorn.workers.ggevent.GeventWorker",
         "gevent_wsgi": "gunicorn.workers.ggevent.GeventPyWSGIWorker",
         "gevent_pywsgi": "gunicorn.workers.ggevent.GeventPyWSGIWorker",
         "tornado": "gunicorn.workers.gtornado.TornadoWorker"}
 
+
+if sys.version_info >= (3, 3):
+    # gaiohttp worker can be used with Python 3.3+ only.
+    SUPPORTED_WORKERS["gaiohttp"] = "gunicorn.workers.gaiohttp.AiohttpWorker"