diff --git a/app/Http/Controllers/Api/V1/ApiController.php b/app/Http/Controllers/Api/V1/ApiController.php
index 9cf18c5..ba8df58 100644
--- a/app/Http/Controllers/Api/V1/ApiController.php
+++ b/app/Http/Controllers/Api/V1/ApiController.php
@@ -3,6 +3,7 @@
 namespace App\Http\Controllers\Api\V1;
 
 use App\Http\Controllers\Controller;
+use App\Models\LoginToken;
 use App\Models\Members\User;
 use Illuminate\Http\Request;
 use Illuminate\Support\Facades\DB;
@@ -110,4 +111,45 @@ public function signup(Request $request)
             return ['user' => $user->only(['id', 'user_id', 'name', 'email', 'phone'])];
         });
     }
+
+    /**
+     * One-Time Token을 사용한 자동 로그인 (MNG → DEV)
+     */
+    public function tokenLogin(Request $request)
+    {
+        $token = $request->input('token');
+
+        if (! $token) {
+            return response()->json(['error' => '토큰이 필요합니다.'], 400);
+        }
+
+        // 토큰 검증
+        $loginToken = LoginToken::findValidToken($token);
+
+        if (! $loginToken) {
+            return response()->json(['error' => '유효하지 않거나 만료된 토큰입니다.'], 401);
+        }
+
+        // 토큰 사용 (1회용 - 사용 후 삭제)
+        $user = $loginToken->consume();
+
+        // 액세스 + 리프레시 토큰 발급
+        $tokens = \App\Services\AuthService::issueTokens($user);
+
+        // 사용자 정보 조회 (테넌트 + 메뉴 포함)
+        $loginInfo = \App\Services\MemberService::getUserInfoForLogin($user->id);
+
+        return response()->json([
+            'message' => '로그인 성공',
+            'access_token' => $tokens['access_token'],
+            'refresh_token' => $tokens['refresh_token'],
+            'token_type' => $tokens['token_type'],
+            'expires_in' => $tokens['expires_in'],
+            'expires_at' => $tokens['expires_at'],
+            'user' => $loginInfo['user'],
+            'tenant' => $loginInfo['tenant'],
+            'menus' => $loginInfo['menus'],
+            'roles' => $loginInfo['roles'],
+        ]);
+    }
 }
diff --git a/app/Models/LoginToken.php b/app/Models/LoginToken.php
new file mode 100644
index 0000000..afea3af
--- /dev/null
+++ b/app/Models/LoginToken.php
@@ -0,0 +1,89 @@
+<?php
+
+namespace App\Models;
+
+use App\Models\Members\User;
+use Illuminate\Database\Eloquent\Model;
+use Illuminate\Database\Eloquent\Relations\BelongsTo;
+use Illuminate\Support\Str;
+
+/**
+ * MNG → DEV 자동 로그인용 One-Time Token 모델
+ */
+class LoginToken extends Model
+{
+    protected $fillable = [
+        'user_id',
+        'token',
+        'expires_at',
+    ];
+
+    protected $casts = [
+        'expires_at' => 'datetime',
+    ];
+
+    /**
+     * 토큰 만료 시간 (분)
+     */
+    public const EXPIRES_IN_MINUTES = 5;
+
+    /**
+     * 사용자 관계
+     */
+    public function user(): BelongsTo
+    {
+        return $this->belongsTo(User::class);
+    }
+
+    /**
+     * 새 토큰 생성
+     */
+    public static function createForUser(int $userId): self
+    {
+        // 기존 토큰 삭제 (해당 사용자)
+        self::where('user_id', $userId)->delete();
+
+        return self::create([
+            'user_id' => $userId,
+            'token' => Str::random(64),
+            'expires_at' => now()->addMinutes(self::EXPIRES_IN_MINUTES),
+        ]);
+    }
+
+    /**
+     * 토큰으로 조회 및 검증
+     */
+    public static function findValidToken(string $token): ?self
+    {
+        return self::where('token', $token)
+            ->where('expires_at', '>', now())
+            ->first();
+    }
+
+    /**
+     * 만료 여부 확인
+     */
+    public function isExpired(): bool
+    {
+        return $this->expires_at->isPast();
+    }
+
+    /**
+     * 토큰 사용 (1회용 - 사용 후 삭제)
+     */
+    public function consume(): User
+    {
+        $user = $this->user;
+        $this->delete();
+
+        return $user;
+    }
+
+    /**
+     * 만료된 토큰 정리
+     */
+    public static function cleanupExpired(): int
+    {
+        return self::where('expires_at', '<', now())->delete();
+    }
+}
diff --git a/database/migrations/2025_12_20_132721_create_login_tokens_table.php b/database/migrations/2025_12_20_132721_create_login_tokens_table.php
new file mode 100644
index 0000000..e93e016
--- /dev/null
+++ b/database/migrations/2025_12_20_132721_create_login_tokens_table.php
@@ -0,0 +1,42 @@
+<?php
+
+use Illuminate\Database\Migrations\Migration;
+use Illuminate\Database\Schema\Blueprint;
+use Illuminate\Support\Facades\Schema;
+
+return new class extends Migration
+{
+    /**
+     * Run the migrations.
+     *
+     * MNG → DEV 자동 로그인용 One-Time Token 테이블
+     */
+    public function up(): void
+    {
+        Schema::create('login_tokens', function (Blueprint $table) {
+            $table->id();
+            $table->unsignedBigInteger('user_id')->comment('사용자 ID');
+            $table->string('token', 64)->unique()->comment('One-Time Token (64자)');
+            $table->timestamp('expires_at')->comment('만료 시간');
+            $table->timestamps();
+
+            // 인덱스
+            $table->index('token');
+            $table->index('expires_at');
+
+            // 외래키 (users 테이블과 연결)
+            $table->foreign('user_id')
+                ->references('id')
+                ->on('users')
+                ->cascadeOnDelete();
+        });
+    }
+
+    /**
+     * Reverse the migrations.
+     */
+    public function down(): void
+    {
+        Schema::dropIfExists('login_tokens');
+    }
+};
diff --git a/routes/api.php b/routes/api.php
index 65d30df..71ab878 100644
--- a/routes/api.php
+++ b/routes/api.php
@@ -107,6 +107,7 @@
         Route::post('login', [ApiController::class, 'login'])->name('v1.users.login');
         Route::middleware('auth:sanctum')->post('logout', [ApiController::class, 'logout'])->name('v1.users.logout');
         Route::post('signup', [ApiController::class, 'signup'])->name('v1.users.signup');
+        Route::post('token-login', [ApiController::class, 'tokenLogin'])->name('v1.auth.token-login');  // MNG → DEV 자동 로그인
         Route::post('refresh', [RefreshController::class, 'refresh'])->name('v1.token.refresh');
         Route::post('register', [RegisterController::class, 'register'])->name('v1.register');