diff --git a/tests/test_appctx.py b/tests/test_appctx.py
index 0c291b87..0146583f 100644
--- a/tests/test_appctx.py
+++ b/tests/test_appctx.py
@@ -111,7 +111,7 @@ class TestAppContext(TestFlask):
         c = app.test_client()
         res = c.get('/')
         assert res.status_code == 200
-        assert res.data == u''
+        assert res.data == b''
         assert called == ['request', 'app']