diff --git a/tests/test_app_factory.py b/tests/test_app_factory.py
new file mode 100644
index 0000000..2803175
--- /dev/null
+++ b/tests/test_app_factory.py
@@ -0,0 +1,31 @@
+import os
+import os.path as op
+import unittest
+
+from nyaa import create_app
+
+
+class CustomConfig(object):
+    DEBUG = True
+    SQLALCHEMY_DATABASE_URI = 'sqlite:///:memory:'
+    SECRET_KEY = '***'  # For DebugToolbar
+    LOG_FILE = op.abspath(op.join(op.dirname(__file__), 'test.log'))
+
+
+class TestAppFactory(unittest.TestCase):
+    def setUp(self):
+        if op.isfile(CustomConfig.LOG_FILE):
+            os.remove(CustomConfig.LOG_FILE)
+
+    def test_create_app(self):
+        # config is usually a class or a module
+        app = create_app(config=CustomConfig)
+
+        self.assertIn('DEBUG', app.config)
+        self.assertTrue(app.config['DEBUG'])
+
+        del app
+
+
+if __name__ == '__main__':
+    unittest.main()