diff --git a/src/main/java/org/ntlab/acanthus_server/entities/AccountJson.java b/src/main/java/org/ntlab/acanthus_server/entities/AccountJson.java
index e306864..2ee48fe 100644
--- a/src/main/java/org/ntlab/acanthus_server/entities/AccountJson.java
+++ b/src/main/java/org/ntlab/acanthus_server/entities/AccountJson.java
@@ -14,15 +14,12 @@
     private Integer uid;
     @JsonProperty("name")
     private String name;
-    @JsonProperty("email")
-    private  String email;
 
     //-----------------------------------------------------------------
     //-----------------------------------------------------------------
     public  AccountJson(Account account){
         this.uid = account.getUid();
         this.name = account.getName();
-        this.email = account.getEmail();
     }
     //-----------------------------------------------------------------
 }
diff --git a/src/main/java/org/ntlab/acanthus_server/models/Accounts.java b/src/main/java/org/ntlab/acanthus_server/models/Accounts.java
index 3aceea6..2c58c6a 100644
--- a/src/main/java/org/ntlab/acanthus_server/models/Accounts.java
+++ b/src/main/java/org/ntlab/acanthus_server/models/Accounts.java
@@ -6,6 +6,7 @@
 import java.util.Collection;
 import java.util.HashMap;
 import java.util.Random;
+import java.util.regex.Pattern;
 
 /*
  * アカウント管理シングルトン
diff --git a/src/main/java/org/ntlab/acanthus_server/resources/accounts/AccountsRest.java b/src/main/java/org/ntlab/acanthus_server/resources/accounts/AccountsRest.java
index c8ac315..8b55d5c 100644
--- a/src/main/java/org/ntlab/acanthus_server/resources/accounts/AccountsRest.java
+++ b/src/main/java/org/ntlab/acanthus_server/resources/accounts/AccountsRest.java
@@ -10,6 +10,7 @@
 import javax.ws.rs.core.MediaType;
 import java.util.ArrayList;
 import java.util.Collection;
+import java.util.regex.Pattern;
 
 @Component
 @Path("/accounts")
@@ -38,7 +39,7 @@
             }
         }
         // 全アカウントの取得
-         else{
+        else {
             for (var account : accounts.getAllAccounts()) {
                 var newAccountJson = new AccountJson(account);
                 accountJsonList.add(newAccountJson);
@@ -82,9 +83,9 @@
     @Produces(MediaType.APPLICATION_JSON)
     public int createAccount(@FormParam("name") String name, @FormParam("email") String email, @FormParam("password") String password) {
 
-        // password: 最低８文字以上の入力
-        var passMinLen = 8;
-        if (password.length() < passMinLen) throw new WebApplicationException(401);
+        // パスワード, メアドが正しく入力されているかチェック
+        if (!isCorrectPassword(password) || !isCorrectEmailAddress(email))
+            throw new WebApplicationException(401);
 
         // すでに同じメールアドレスが存在しているか
         var existAccount = accounts.getAccountByEmail(email);
@@ -95,6 +96,40 @@
 
         return newAccount.getUid();
     }
+
+    //-----------------------------------------------------------------
+    //-----------------------------------------------------------------
+    // 正しいメールアドレスが登録されているか判定
+    //-----------------------------------------------------------------
+
+    /**
+     * @param emailAddress メアド
+     */
+    @SuppressWarnings("{unchecked}") // 正規表現の警告無視
+    private boolean isCorrectEmailAddress(String emailAddress) {
+
+        var aText =  "[a-zA-Z0-9_!#¥¥$¥¥%&'*+/=?¥¥^`{}~|¥¥-]+";
+        var dotAtom = aText + "(?:\\." + aText + "+)*";
+        var regularExpression = "^" + dotAtom + "@" + dotAtom + "$";
+
+        var pattern = Pattern.compile(regularExpression);
+        var matcher = pattern.matcher(emailAddress);
+
+        return matcher.find();
+    }
+
+    //-----------------------------------------------------------------
+    // 正しいパスワードが入力されているかチェック
+    //-----------------------------------------------------------------
+
+    /**
+     * @param password パスワード
+     */
+    private boolean isCorrectPassword(String password) {
+        // password: 最低８文字以上の入力
+        var passMinLen = 8;
+        return (passMinLen <= password.length());
+    }
     //-----------------------------------------------------------------
 
 }
diff --git a/src/main/java/org/ntlab/acanthus_server/resources/accounts/LoginRest.java b/src/main/java/org/ntlab/acanthus_server/resources/accounts/LoginRest.java
index bce300e..cf3ab3b 100644
--- a/src/main/java/org/ntlab/acanthus_server/resources/accounts/LoginRest.java
+++ b/src/main/java/org/ntlab/acanthus_server/resources/accounts/LoginRest.java
@@ -47,7 +47,7 @@
         if (searchAccount == null) throw new WebApplicationException(400);
         if (!searchAccount.isMatchedPassword(password)) throw new WebApplicationException(401);
 
-        searchAccount.updateToken();
+        searchAccount.updateToken(); // トークンをアカウントに設定
         return searchAccount.getToken();
     }
     //-----------------------------------------------------------