diff --git a/locales/installer/ko-kr.json b/locales/installer/ko-kr.json
index fc5ac46..1bf7ef5 100644
--- a/locales/installer/ko-kr.json
+++ b/locales/installer/ko-kr.json
@@ -205,6 +205,7 @@
   },
   "log": {
     "manifestDownload": "manifest 다운로드: {{url}}",
+    "downloadRetry": "다운로드 일시 오류({{reason}}) — {{attempt}}번째 재시도, {{secs}}초 후",
     "packLoadFail": "pack 로드 실패 ({{file}}): {{message}}",
     "packsLoaded": "로드된 음악퀴즈: {{count}}개",
     "selectedPack": "선택: {{key}}",
diff --git a/package.json b/package.json
index 2127731..7e30ae4 100644
--- a/package.json
+++ b/package.json
@@ -1,6 +1,6 @@
 {
   "name": "minecraft-music-quiz-installer",
-  "version": "0.4.12",
+  "version": "0.4.13",
   "description": "마인크래프트 음악퀴즈 간편설치기 + 관리 사이트",
   "main": "dist/installer/main.js",
   "scripts": {
diff --git a/src/installer/main.ts b/src/installer/main.ts
index 954addb..f3781d5 100644
--- a/src/installer/main.ts
+++ b/src/installer/main.ts
@@ -109,29 +109,61 @@ process.on('unhandledRejection', (reason) => {
   try { sendLog(t('log.internalError', { message: reason instanceof Error ? reason.message : String(reason) })) } catch {}
 })
 
-function fetchBuffer(url: string): Promise<Buffer> {
+// 너무 빠르게/자주 요청해 생기는 일시적 오류(429 Too Many Requests, 5xx, 네트워크
+// 끊김/타임아웃 등)는 잠깐 쉬고 몇 번 다시 시도한다. 403 도 일부 CDN 이 rate-limit 에
+// 쓰므로 포함. 그 외 4xx(404 등)나 재시도 소진 시에는 그대로 실패.
+const DOWNLOAD_TRANSIENT_CODES = new Set([403, 408, 425, 429, 500, 502, 503, 504])
+const DOWNLOAD_MAX_RETRIES = 3
+const DOWNLOAD_MAX_BACKOFF_MS = 30000
+
+/** Retry-After 헤더(초 또는 HTTP-date) → 대기 ms. 못 읽으면 null. */
+function parseRetryAfterMs(h: string | string[] | undefined): number | null {
+  if (!h) return null
+  const v = Array.isArray(h) ? h[0] : h
+  const secs = Number(v)
+  if (Number.isFinite(secs)) return Math.min(DOWNLOAD_MAX_BACKOFF_MS, Math.max(0, secs * 1000))
+  const date = Date.parse(v)
+  if (!Number.isNaN(date)) return Math.min(DOWNLOAD_MAX_BACKOFF_MS, Math.max(0, date - Date.now()))
+  return null
+}
+
+function fetchBuffer(url: string, redirects = 0, attempt = 0): Promise<Buffer> {
   return new Promise((resolve, reject) => {
     const target = new URL(url)
     const transport = target.protocol === 'https:' ? https : http
+    const retryLater = (headerDelay: number | null, reason: string): void => {
+      const backoff = Math.min(DOWNLOAD_MAX_BACKOFF_MS, 1000 * 2 ** attempt) + Math.floor(Math.random() * 500)
+      const delay = headerDelay ?? backoff
+      sendLog(t('log.downloadRetry', { reason, attempt: attempt + 1, secs: Math.ceil(delay / 1000) }))
+      sleep(delay).then(() => fetchBuffer(url, redirects, attempt + 1).then(resolve, reject))
+    }
     const request = transport.get(target, { timeout: 30000 }, (response) => {
-      if (response.statusCode === 301 || response.statusCode === 302) {
-        const redirect = response.headers.location
-        if (redirect) {
-          response.resume()
-          fetchBuffer(new URL(redirect, target).toString()).then(resolve, reject)
-          return
-        }
-      }
-      if ((response.statusCode ?? 0) >= 400) {
+      const code = response.statusCode ?? 0
+      if ((code === 301 || code === 302 || code === 303 || code === 307 || code === 308) && response.headers.location) {
         response.resume()
-        reject(new Error(`HTTP ${response.statusCode}`))
+        if (redirects > 8) { reject(new Error(`HTTP ${code} (too many redirects)`)); return }
+        fetchBuffer(new URL(response.headers.location, target).toString(), redirects + 1, attempt).then(resolve, reject)
+        return
+      }
+      if (DOWNLOAD_TRANSIENT_CODES.has(code) && attempt < DOWNLOAD_MAX_RETRIES) {
+        response.resume()
+        retryLater(parseRetryAfterMs(response.headers['retry-after']), `HTTP ${code}`)
+        return
+      }
+      if (code >= 400) {
+        response.resume()
+        reject(new Error(`HTTP ${code}`))
         return
       }
       const chunks: Buffer[] = []
       response.on('data', (chunk: Buffer) => chunks.push(chunk))
       response.on('end', () => resolve(Buffer.concat(chunks)))
     })
-    request.on('error', reject)
+    request.on('error', (err) => {
+      // 연결 끊김/리셋 등 네트워크 오류도 몇 번은 재시도.
+      if (attempt < DOWNLOAD_MAX_RETRIES) { retryLater(null, (err as Error).message); return }
+      reject(err)
+    })
     request.on('timeout', () => request.destroy(new Error(t('errors.requestTimeout'))))
   })
 }