diff --git a/app/routers/yudao_aiot_alarm.py b/app/routers/yudao_aiot_alarm.py
index eb1d60b..f8a46b9 100644
--- a/app/routers/yudao_aiot_alarm.py
+++ b/app/routers/yudao_aiot_alarm.py
@@ -22,7 +22,7 @@ from app.yudao_compat import YudaoResponse, get_current_user
 from app.services.alarm_event_service import get_alarm_event_service, AlarmEventService
 from app.services.notification_service import get_notification_service
 from app.services.oss_storage import get_oss_storage
-from app.schemas import EdgeAlarmReport
+from app.schemas import EdgeAlarmReport, EdgeAlarmResolve
 from app.utils.logger import logger
 
 router = APIRouter(prefix="/admin-api/aiot/alarm", tags=["AIoT-告警"])
@@ -304,6 +304,28 @@ async def edge_alarm_report(
     })
 
 
+@router.post("/edge/resolve")
+async def edge_alarm_resolve(
+    resolve: EdgeAlarmResolve,
+    service: AlarmEventService = Depends(get_alarm_event_service),
+):
+    """
+    边缘端告警结束通知
+
+    Edge 在人员回岗确认或非工作时间到达时调用此接口，
+    更新告警的 duration_ms 和 last_frame_time。
+    """
+    success = service.resolve_alarm(
+        alarm_id=resolve.alarm_id,
+        duration_ms=resolve.duration_ms,
+        last_frame_time=resolve.last_frame_time,
+        resolve_type=resolve.resolve_type,
+    )
+    if not success:
+        return YudaoResponse.error(404, "告警不存在")
+    return YudaoResponse.success(True)
+
+
 # ==================== 辅助函数 ====================
 
 OPS_ALARM_URL = "http://192.168.0.104:48080/admin-api/ops/alarm/receive"
diff --git a/app/schemas.py b/app/schemas.py
index 6a1c3a6..d2e022f 100644
--- a/app/schemas.py
+++ b/app/schemas.py
@@ -126,3 +126,11 @@ class EdgeAlarmReport(BaseModel):
     algorithm_code: Optional[str] = Field(None, max_length=64, description="算法编码")
     confidence_score: Optional[float] = Field(None, ge=0, le=1, description="置信度 0-1")
     ext_data: Optional[Dict[str, Any]] = Field(None, description="扩展数据 (bbox/target_class 等)")
+
+
+class EdgeAlarmResolve(BaseModel):
+    """边缘端告警结束事件"""
+    alarm_id: str = Field(..., description="告警ID")
+    duration_ms: int = Field(..., ge=0, description="持续时长(毫秒)")
+    last_frame_time: str = Field(..., description="结束时间 ISO8601")
+    resolve_type: str = Field(..., description="结束类型: person_returned/non_work_time")
diff --git a/app/services/alarm_event_service.py b/app/services/alarm_event_service.py
index c627a59..af83b48 100644
--- a/app/services/alarm_event_service.py
+++ b/app/services/alarm_event_service.py
@@ -171,12 +171,21 @@ class AlarmEventService:
 
             alarm_type = data.get("alarm_type", "unknown")
             alarm_level = data.get("alarm_level")
+            ext_data = data.get("ext_data") or {}
             if alarm_level is None:
                 # 从 ext_data 取 duration_ms
-                ext_data = data.get("ext_data") or {}
                 duration_ms = ext_data.get("duration_ms")
                 alarm_level = _determine_alarm_level(alarm_type, confidence or 0, duration_ms)
 
+            # 解析 first_frame_time（离岗开始时间，由 Edge 在 ext_data 中传递）
+            first_frame_time = None
+            first_frame_time_str = ext_data.get("first_frame_time")
+            if first_frame_time_str:
+                try:
+                    first_frame_time = datetime.fromisoformat(first_frame_time_str.replace("Z", "+00:00"))
+                except ValueError:
+                    first_frame_time = None
+
             alarm = AlarmEvent(
                 alarm_id=alarm_id,
                 alarm_type=alarm_type,
@@ -184,12 +193,14 @@ class AlarmEventService:
                 device_id=data.get("device_id", "unknown"),
                 scene_id=data.get("scene_id"),
                 event_time=event_time,
+                first_frame_time=first_frame_time,
+                duration_ms=ext_data.get("duration_ms"),
                 alarm_level=alarm_level,
                 confidence_score=confidence,
                 alarm_status="NEW",
                 handle_status="UNHANDLED",
-                snapshot_url=data.get("snapshot_url"),  # COS object_key
-                edge_node_id=data.get("ext_data", {}).get("edge_node_id") if data.get("ext_data") else None,
+                snapshot_url=data.get("snapshot_url"),
+                edge_node_id=ext_data.get("edge_node_id"),
             )
 
             db.add(alarm)
@@ -520,6 +531,46 @@ class AlarmEventService:
         finally:
             db.close()
 
+    def resolve_alarm(self, alarm_id: str, duration_ms: int, last_frame_time: str, resolve_type: str) -> bool:
+        """更新告警的持续时长和结束时间"""
+        db = get_session()
+        try:
+            alarm = db.query(AlarmEvent).filter(AlarmEvent.alarm_id == alarm_id).first()
+            if not alarm:
+                return False
+
+            alarm.duration_ms = duration_ms
+
+            # 解析 last_frame_time
+            try:
+                alarm.last_frame_time = datetime.fromisoformat(last_frame_time.replace("Z", "+00:00"))
+            except Exception:
+                alarm.last_frame_time = datetime.now(timezone.utc)
+
+            # 如果是人员回岗，标记为自动关闭
+            if resolve_type == "person_returned":
+                alarm.alarm_status = "CLOSED"
+                alarm.handle_status = "DONE"
+                alarm.handle_remark = "人员回岗自动关闭"
+                alarm.handled_at = datetime.now(timezone.utc)
+            elif resolve_type == "non_work_time":
+                alarm.alarm_status = "CLOSED"
+                alarm.handle_status = "DONE"
+                alarm.handle_remark = "非工作时间自动关闭"
+                alarm.handled_at = datetime.now(timezone.utc)
+
+            alarm.updated_at = datetime.now(timezone.utc)
+            db.commit()
+
+            logger.info(f"告警已更新结束信息: {alarm_id}, duration={duration_ms}ms, type={resolve_type}")
+            return True
+        except Exception as e:
+            db.rollback()
+            logger.error(f"更新告警结束信息失败: {e}")
+            return False
+        finally:
+            db.close()
+
     def save_llm_analysis(
         self,
         alarm_id: str,