diff --git a/services-preview/markets-service/docs/ORDER_BOOK_AUDIT.md b/services-preview/markets-service/docs/ORDER_BOOK_AUDIT.md
index c46445da..7e501db7 100644
--- a/services-preview/markets-service/docs/ORDER_BOOK_AUDIT.md
+++ b/services-preview/markets-service/docs/ORDER_BOOK_AUDIT.md
@@ -93,6 +93,19 @@ if last_update_id < prev_id:
 | `order_book_full_written` | full 写入行数 |
 | `order_book_write_errors` | 写入错误次数 |
 | `order_book_out_of_order` | 乱序跳过次数 |
+| `delay_avg/max` | 数据延迟 (ms) |
+
+### 3.4 健康检查
+
+- **延迟监控**: `receipt_ts - event_ts`，超 5s 告警
+- **心跳检测**: 30s 无数据告警
+- **统计日志**: 每 60s 输出
+
+```
+INFO 统计: received=12000, tick=4000, full=800, errors=0, oos=0, delay_avg=50ms, delay_max=200ms
+WARN 心跳超时: 35s 无数据
+WARN 高延迟: BTCUSDT delay=6000ms
+```
 
 ---
 
@@ -175,3 +188,4 @@ ORDER_BOOK_SYMBOLS=            # 可选，逗号分隔
 | 2026-01-09 | 修复: 原始格式 `[["price","qty"],...]` |
 | 2026-01-09 | 修复: lastUpdateId 采集、乱序检测 |
 | 2026-01-09 | 增强: 错误日志、统计指标 |
+| 2026-01-09 | 增强: 延迟监控、心跳检测 |
diff --git a/services-preview/markets-service/src/crypto/collectors/order_book.py b/services-preview/markets-service/src/crypto/collectors/order_book.py
index 42c48dc4..a375a5cc 100644
--- a/services-preview/markets-service/src/crypto/collectors/order_book.py
+++ b/services-preview/markets-service/src/crypto/collectors/order_book.py
@@ -271,6 +271,8 @@ async def _on_book(self, book, receipt_ts: float) -> None:
             return
 
         now = time.time()
+        self._last_msg_time = now  # 心跳更新
+        
         ts = datetime.fromtimestamp(book.timestamp, tz=timezone.utc)
         bids_dict = book.book.bids.to_dict()
         asks_dict = book.book.asks.to_dict()
@@ -278,6 +280,15 @@ async def _on_book(self, book, receipt_ts: float) -> None:
         # 提取原始元数据 (cryptofeed: sequence_number = lastUpdateId)
         last_update_id = getattr(book, 'sequence_number', None)
         
+        # 延迟监控: receipt_ts - event_ts
+        delay_ms = int((receipt_ts - book.timestamp) * 1000)
+        if delay_ms > 0:
+            self._stats["total_delay_ms"] += delay_ms
+            if delay_ms > self._stats["max_delay_ms"]:
+                self._stats["max_delay_ms"] = delay_ms
+            if delay_ms > 5000:  # 延迟超过 5 秒告警
+                logger.warning("高延迟: %s delay=%dms", sym, delay_ms)
+        
         self._stats["received"] += 1
         
         # 乱序检测: 如果 lastUpdateId 倒退则跳过
@@ -473,10 +484,15 @@ async def _stats_reporter():
             while True:
                 await asyncio.sleep(60)
                 s = self._stats
+                avg_delay = s["total_delay_ms"] // max(s["received"], 1)
+                # 心跳检测
+                idle_sec = int(time.time() - self._last_msg_time) if self._last_msg_time > 0 else 0
+                if idle_sec > 30:
+                    logger.warning("心跳超时: %ds 无数据", idle_sec)
                 logger.info(
-                    "统计: received=%d, tick=%d, full=%d, errors=%d, out_of_order=%d",
+                    "统计: received=%d, tick=%d, full=%d, errors=%d, oos=%d, delay_avg=%dms, delay_max=%dms",
                     s["received"], s["written_tick"], s["written_full"],
-                    s["errors"], s["out_of_order"]
+                    s["errors"], s["out_of_order"], avg_delay, s["max_delay_ms"]
                 )
 
         try:
@@ -492,10 +508,11 @@ async def _stats_reporter():
     def _log_final_stats(self) -> None:
         """输出最终统计"""
         s = self._stats
+        avg_delay = s["total_delay_ms"] // max(s["received"], 1)
         logger.info(
-            "采集结束统计: received=%d, tick=%d, full=%d, errors=%d, out_of_order=%d",
+            "采集结束: received=%d, tick=%d, full=%d, errors=%d, oos=%d, delay_avg=%dms, delay_max=%dms",
             s["received"], s["written_tick"], s["written_full"],
-            s["errors"], s["out_of_order"]
+            s["errors"], s["out_of_order"], avg_delay, s["max_delay_ms"]
         )
 
     async def _final_flush(self) -> None: