diff --git a/setup.cfg b/setup.cfg
index 581b2a7..e469e17 100644
--- a/setup.cfg
+++ b/setup.cfg
@@ -36,6 +36,9 @@ package_dir =
 # entry_pointの設定を外部ファイルにする場合
 # entry_points = file: entry_points.cfg
 
+# テストモジュールのあるディレクトリ
+test_suite=tests
+
 # options.packages = find: の引数
 [options.packages.find]
 where=src
diff --git a/src/imagenate/sample.py b/src/imagenate/sample.py
index 5d0fbb8..d58c878 100644
--- a/src/imagenate/sample.py
+++ b/src/imagenate/sample.py
@@ -1,2 +1,2 @@
 def hello():
-    print('hello')
\ No newline at end of file
+    return "hello"

diff --git a/src/tests/__init__.py b/src/tests/__init__.py
new file mode 100644
index 0000000..e69de29
diff --git a/src/tests/test_imagenate.py b/src/tests/test_imagenate.py
new file mode 100644
index 0000000..108890b
--- /dev/null
+++ b/src/tests/test_imagenate.py
@@ -0,0 +1,7 @@
+import unittest
+import imagenate
+
+class TestImagenate(unittest.TestCase):
+
+    def test_hello(self):
+        self.assertEqual(imagenate.hello(), 'hello', 'hello is misssing')

unittest
<!-- Edit the body of your new issue then click the ✓ "Create Issue" button in the top right of the editor. The first line will be the issue title. Assignees and Labels follow after a blank line. Leave an empty line before beginning the body of the issue. -->
src/tests/test_imagenate.py::TestImagenate::test_hello