diff --git a/app/Services/Video/GeminiScriptService.php b/app/Services/Video/GeminiScriptService.php
index e354fded..f2da6a40 100644
--- a/app/Services/Video/GeminiScriptService.php
+++ b/app/Services/Video/GeminiScriptService.php
@@ -2,18 +2,21 @@
 
 namespace App\Services\Video;
 
+use App\Models\System\AiConfig;
+use App\Services\GoogleCloudService;
 use Illuminate\Support\Facades\Http;
 use Illuminate\Support\Facades\Log;
 
 class GeminiScriptService
 {
-    private string $apiKey;
+    private ?AiConfig $config = null;
 
-    private string $model = 'gemini-2.5-flash';
+    private GoogleCloudService $googleCloud;
 
-    public function __construct()
+    public function __construct(GoogleCloudService $googleCloud)
     {
-        $this->apiKey = config('services.gemini.api_key', '');
+        $this->googleCloud = $googleCloud;
+        $this->config = AiConfig::getActiveGemini();
     }
 
     /**
@@ -111,22 +114,19 @@ public function generateScenario(string $title, string $keyword = ''): array
     }
 
     /**
-     * Gemini API 호출
+     * Gemini API 호출 (AiConfig 기반 - API Key / Vertex AI 자동 분기)
      */
     private function callGemini(string $prompt): ?string
     {
-        if (empty($this->apiKey)) {
-            Log::error('GeminiScriptService: API 키가 설정되지 않았습니다.');
+        if (! $this->config) {
+            Log::error('GeminiScriptService: 활성화된 Gemini 설정이 없습니다. (시스템 > AI 설정 확인)');
 
             return null;
         }
 
         try {
-            $url = "https://generativelanguage.googleapis.com/v1beta/models/{$this->model}:generateContent";
-
-            $response = Http::withHeaders([
-                'x-goog-api-key' => $this->apiKey,
-            ])->timeout(60)->post($url, [
+            $model = $this->config->model ?: 'gemini-2.5-flash';
+            $body = [
                 'contents' => [
                     [
                         'parts' => [
@@ -139,12 +139,41 @@ private function callGemini(string $prompt): ?string
                     'maxOutputTokens' => 4096,
                     'responseMimeType' => 'application/json',
                 ],
-            ]);
+            ];
+
+            if ($this->config->isVertexAi()) {
+                // Vertex AI 방식 (서비스 계정 OAuth)
+                $accessToken = $this->googleCloud->getAccessToken();
+                if (! $accessToken) {
+                    Log::error('GeminiScriptService: Vertex AI 액세스 토큰 획득 실패');
+
+                    return null;
+                }
+
+                $projectId = $this->config->getProjectId();
+                $region = $this->config->getRegion();
+                $url = "https://{$region}-aiplatform.googleapis.com/v1/projects/{$projectId}/locations/{$region}/publishers/google/models/{$model}:generateContent";
+
+                // Vertex AI에서는 role 필수
+                $body['contents'][0]['role'] = 'user';
+
+                $response = Http::withToken($accessToken)
+                    ->timeout(60)
+                    ->post($url, $body);
+            } else {
+                // API Key 방식
+                $apiKey = $this->config->api_key;
+                $baseUrl = $this->config->base_url ?? 'https://generativelanguage.googleapis.com/v1beta';
+                $url = "{$baseUrl}/models/{$model}:generateContent?key={$apiKey}";
+
+                $response = Http::timeout(60)->post($url, $body);
+            }
 
             if (! $response->successful()) {
                 Log::error('GeminiScriptService: API 호출 실패', [
                     'status' => $response->status(),
                     'body' => $response->body(),
+                    'auth_type' => $this->config->isVertexAi() ? 'vertex_ai' : 'api_key',
                 ]);
 
                 return null;