diff --git a/intc-modules/intc-iot/src/main/java/com/intc/iot/handler/DeviceDataHandler.java b/intc-modules/intc-iot/src/main/java/com/intc/iot/handler/DeviceDataHandler.java
index d853d7c..97b3590 100644
--- a/intc-modules/intc-iot/src/main/java/com/intc/iot/handler/DeviceDataHandler.java
+++ b/intc-modules/intc-iot/src/main/java/com/intc/iot/handler/DeviceDataHandler.java
@@ -47,6 +47,9 @@ import java.util.Date;
 import java.util.HashMap;
 import java.util.List;
 import java.util.Map;
+import java.util.concurrent.Executors;
+import java.util.concurrent.ScheduledExecutorService;
+import java.util.concurrent.TimeUnit;
 
 /**
  * 设备数据处理器
@@ -62,6 +65,17 @@ public class DeviceDataHandler {
     public static final String PENDING_SOLAR_SALINITY_KEY_PREFIX = "device:pending:solar:salinity:";
     private static final int DEVICE_TYPE_SOLAR_CONTROLLER = 3;
 
+    /**
+     * 太阳能盐度补发专用调度线程池（daemon线程，避免阻止JVM退出）
+     * 用于设备上线后延迟执行属性下发，确保设备已完成 MQTT 订阅
+     */
+    private static final ScheduledExecutorService SOLAR_SALINITY_SCHEDULER =
+        Executors.newSingleThreadScheduledExecutor(r -> {
+            Thread t = new Thread(r, "solar-salinity-flush");
+            t.setDaemon(true);
+            return t;
+        });
+
     /**
      * TDengine 服务，用于存储设备时序数据
      */
@@ -960,7 +974,12 @@ public class DeviceDataHandler {
             log.info("[离线告警] 设备已上线，取消离线告警: {}", deviceName);
         }
 
-        flushPendingSolarSalinity(deviceName, "生命周期上线");
+        // 异步延迟 1.5 秒补发缓存盐度：设备刚上线时尚未完成 MQTT 订阅，
+        // 立即下发属性会失败，等待 1.5 秒让设备完成订阅后再下发
+        SOLAR_SALINITY_SCHEDULER.schedule(
+            () -> flushPendingSolarSalinity(deviceName, "生命周期上线"),
+            1500L, TimeUnit.MILLISECONDS
+        );
 
         // 同步更新 Device.warnCode，清除离线和休眠标志位
         setDeviceWarnCodeBit(deviceName, DefineDeviceWarnCode.DeviceOffline, false);