diff --git a/README.md b/README.md
index 753b2c4..f555760 100644
--- a/README.md
+++ b/README.md
@@ -32,6 +32,7 @@ python -m playwright install-deps chromium
 | `datasource/` | 存放 SAP Analytics 导出的 CSV 文件 |
 | `downloads/` | 本地临时下载目录（上传 DSM 后自动清理） |
 | `error_log.txt` | 错误日志，每次批量运行时重置 |
+| `failed_tickets.csv` | 失败的 Ticket ID 列表，可用于下次重试 |
 
 ---
 
@@ -83,11 +84,20 @@ python sap-c4c-AttachmentFolder.py ... --json
 python batch_download.py
 ```
 
-- 默认读取 CSV 第二列的 Ticket ID，取前 10 个
+- 读取 datasource 目录下 CSV/xlsx 的第二列，获取所有 Ticket ID
 - 最多 5 个任务并行执行
 - 每个 Ticket 使用独立子目录 `downloads/{ticket_id}`，避免并行冲突
 - 上传 DSM 完成后自动清理本地文件和子目录
-- 错误记录到 `error_log.txt`
+- 错误记录到 `error_log.txt`，失败的 Ticket ID 保存到 `failed_tickets.csv`
+
+### 重试失败的 Ticket
+
+将上一次运行生成的 `failed_tickets.csv` 移动到 `datasource/` 目录，然后重新运行：
+
+```bash
+mv failed_tickets.csv datasource/
+python batch_download.py
+```
 
 ### 修改并行数或 Ticket 数量
 
diff --git a/batch_download.py b/batch_download.py
index 5fd2e6d..b70cc51 100644
--- a/batch_download.py
+++ b/batch_download.py
@@ -24,9 +24,12 @@ WORKERS     = 5
 
 SCRIPT      = os.path.join(os.path.dirname(__file__), "sap-c4c-AttachmentFolder.py")
 ERROR_LOG   = os.path.join(os.path.dirname(__file__), "error_log.txt")
+FAILED_CSV  = os.path.join(os.path.dirname(__file__), "failed_tickets.csv")
 DATASOURCE  = os.path.join(os.path.dirname(__file__), "datasource")
 
 print_lock = threading.Lock()
+failed_lock = threading.Lock()
+failed_ids = set()
 # ─────────────────────────────────────────────────────────────────────────────
 
 
@@ -67,6 +70,11 @@ def log_error(ticket_id, message):
     ts = datetime.datetime.now().strftime("%Y-%m-%d %H:%M:%S")
     with open(ERROR_LOG, "a", encoding="utf-8") as f:
         f.write(f"[{ts}] Ticket {ticket_id}: {message}\n")
+    with failed_lock:
+        if ticket_id not in failed_ids:
+            failed_ids.add(ticket_id)
+            with open(FAILED_CSV, "a", encoding="utf-8", newline="") as f:
+                csv.writer(f).writerow([ticket_id])
 
 
 def run_ticket(ticket_id, index, total):
@@ -130,16 +138,19 @@ def run_ticket(ticket_id, index, total):
 
 
 def main():
+    global failed_ids
     print("读取 Ticket ID ...")
-    ids = get_ticket_ids(10)
+    ids = get_ticket_ids()
     if not ids:
         print("未找到任何 Ticket ID，请检查 datasource 目录")
         sys.exit(1)
 
     print(f"共 {len(ids)} 个 Ticket: {', '.join(ids)}")
 
-    # 清空/创建 error_log
+    # 清空/创建 error_log 和 failed_tickets.csv
     open(ERROR_LOG, "w").close()
+    open(FAILED_CSV, "w", encoding="utf-8", newline="").close()
+    failed_ids.clear()
 
     with ThreadPoolExecutor(max_workers=WORKERS) as executor:
         futures = {executor.submit(run_ticket, tid, i, len(ids)): tid
@@ -148,10 +159,12 @@ def main():
             future.result()  # 触发异常传播（已在 run_ticket 内处理）
 
     print("\n全部完成。")
-    if os.path.getsize(ERROR_LOG) > 0:
-        print(f"有错误，详见 {ERROR_LOG}")
+    if failed_ids:
+        print(f"失败 {len(failed_ids)} 个 Ticket，已保存到 {FAILED_CSV}")
+        if os.path.getsize(ERROR_LOG) > 0:
+            print(f"错误详情见 {ERROR_LOG}")
     else:
-        print("无错误。")
+        print("全部成功，无失败。")
 
 
 if __name__ == "__main__":