diff --git a/src/main/java/org/ntlab/tampoposerver/repositories/UserRepository.java b/src/main/java/org/ntlab/tampoposerver/repositories/UserRepository.java
index c65beaa..f4e34eb 100644
--- a/src/main/java/org/ntlab/tampoposerver/repositories/UserRepository.java
+++ b/src/main/java/org/ntlab/tampoposerver/repositories/UserRepository.java
@@ -35,6 +35,15 @@
         return u;
     }
 
+    public ArrayList<String> getAllEmails() {
+        ArrayList<String> emails = new ArrayList<>();
+        for (String key : userMap.keySet()) {
+            User user = getUser(key);
+            emails.add(user.getEmail());
+        }
+        return emails;
+    }
+
     public User deleteUser(String userId) {//ユーザー情報の削除
         return userMap.remove(userId);
     }