diff --git a/bin/heat-api-cloudwatch b/bin/heat-api-cloudwatch
index 155a4d48f..6a53a43c5 100755
--- a/bin/heat-api-cloudwatch
+++ b/bin/heat-api-cloudwatch
@@ -64,5 +64,5 @@ if __name__ == '__main__':
         server = wsgi.Server()
         server.start(app, cfg.CONF, default_port=port)
         server.wait()
-    except RuntimeError, e:
+    except RuntimeError as e:
         sys.exit("ERROR: %s" % e)