diff --git a/fastbee-service/fastbee-iot-service/src/main/java/com/fastbee/iot/service/impl/DeviceServiceImpl.java b/fastbee-service/fastbee-iot-service/src/main/java/com/fastbee/iot/service/impl/DeviceServiceImpl.java
index d9ec3eda..8ff18684 100644
--- a/fastbee-service/fastbee-iot-service/src/main/java/com/fastbee/iot/service/impl/DeviceServiceImpl.java
+++ b/fastbee-service/fastbee-iot-service/src/main/java/com/fastbee/iot/service/impl/DeviceServiceImpl.java
@@ -1026,24 +1026,12 @@ public class DeviceServiceImpl implements IDeviceService {
         if (CollectionUtils.isEmpty(list)) {
             return new ArrayList<>();
         }
-        List<String> serialNumberList;
-        SysUser user = getLoginUser().getUser();
-        if (null != user.getDept()) {
-            Long tenantId = user.getDept().getDeptUserId();
-            serialNumberList = list.stream().filter(d -> tenantId.equals(d.getTenantId()))
-                    .map(DeviceShortOutput::getSerialNumber).collect(Collectors.toList());
-        } else {
-            serialNumberList = list.stream().map(DeviceShortOutput::getSerialNumber).collect(Collectors.toList());
+        Integer entrance = null == device ? null : device.getEntrance();
+        // 未处理告警数(alertCount)只有详情，根据产品查询设备详情 entrance=4
+        if (Integer.valueOf(4).equals(entrance)) {
+            fillAlertCount(list);
         }
-        if (!CollectionUtils.isEmpty(serialNumberList)) {
-            List<DeviceAlertCount> alist = alertLogService.selectDeviceAlertCount(serialNumberList);
-            for (DeviceAlertCount item : alist) {
-                list.stream()
-                        .filter(it -> Objects.equals(it.getSerialNumber(), item.getSerialNumber()))
-                        .forEach(it -> it.setAlertCount(item));
-            }
-        }
-        fillShortListLatestReportTime(list, device.getEntrance());
+        fillShortListLatestReportTime(list, entrance);
         long took = System.currentTimeMillis() - startTime;
         if (took > 1000L) {
             log.warn("selectDeviceShortList took: {}", took);
@@ -1051,6 +1039,39 @@ public class DeviceServiceImpl implements IDeviceService {
         return list;
     }
 
+    /**
+     * 回填设备未处理告警数（DeviceShortOutput#alertCount）。
+     * <p>
+     * 只统计当前登录用户自己租户的设备：存在部门时按 dept.deptUserId 过滤，
+     * 因此「查询下级机构」带出来的下级机构设备不会带告警徽标。
+     */
+    private void fillAlertCount(List<DeviceShortOutput> list) {
+        SysUser user = getLoginUser().getUser();
+        Long deptUserId = null != user.getDept() ? user.getDept().getDeptUserId() : null;
+        List<String> serialNumberList = list.stream()
+                .filter(d -> null == deptUserId || deptUserId.equals(d.getTenantId()))
+                .map(DeviceShortOutput::getSerialNumber)
+                .collect(Collectors.toList());
+        if (CollectionUtils.isEmpty(serialNumberList)) {
+            return;
+        }
+        List<DeviceAlertCount> alertCountList = alertLogService.selectDeviceAlertCount(serialNumberList);
+        if (CollectionUtils.isEmpty(alertCountList)) {
+            return;
+        }
+        // 先按 serialNumber 建索引再回填，避免原先的嵌套 stream 匹配（O(设备数 × 告警行数)）
+        Map<String, DeviceAlertCount> alertCountMap = new HashMap<>(alertCountList.size());
+        for (DeviceAlertCount item : alertCountList) {
+            alertCountMap.put(item.getSerialNumber(), item);
+        }
+        for (DeviceShortOutput row : list) {
+            DeviceAlertCount alertCount = alertCountMap.get(row.getSerialNumber());
+            if (null != alertCount) {
+                row.setAlertCount(alertCount);
+            }
+        }
+    }
+
     /**
      * 查询当前用户可见设备统计（与 shortList 相同范围）
      */