diff --git a/vd960DBN/BLE/OnlyUpdateApp_Peripheral/APP/net_srv.c b/vd960DBN/BLE/OnlyUpdateApp_Peripheral/APP/net_srv.c
index 730d87a..a21e55d 100644
--- a/vd960DBN/BLE/OnlyUpdateApp_Peripheral/APP/net_srv.c
+++ b/vd960DBN/BLE/OnlyUpdateApp_Peripheral/APP/net_srv.c
@@ -578,28 +578,15 @@ uint8_t i;
         return;
     }
     
-    // IoT MQTT mode — inline MQTT handling (ref: DBN101GA)
+    // IoT MQTT mode — delegate all socket events to iot_mqtt_srv
+    // (2026-07-23 修复: 旧 mqtt_connect/mqtt_data_manage 与 IoT 栈抢 socket, 致双 CONNECT → broker 踢线 → 频繁 initialize)
     if (g_sub_code_enable.iot_enable) {
-        if (intstat & SINT_STAT_RECV) {
-            mqtt_data_manage(socketid);
-        }
-        if (intstat & SINT_STAT_CONNECT) {
 #if KEEPLIVE_ENABLE
+        if (intstat & SINT_STAT_CONNECT) {
             WCHNET_SocketSetKeepLive(socketid, ENABLE);
+        }
 #endif
-            WCHNET_ModifyRecvBuf(socketid, (uint32_t)SocketRecvBuf[socketid], RECE_BUF_LEN);
-            PRINT("TCP Connect Success (MQTT)\n");
-            mqtt_connect();
-        }
-        if (intstat & SINT_STAT_DISCONNECT) {
-            PRINT("TCP Disconnect (MQTT)\n");
-            g_iot_state = IOT_STATE_DISCONNECTED;
-            g_net_state.flag = 1;
-        }
-        if (intstat & SINT_STAT_TIM_OUT) {
-            PRINT("TCP Timeout (MQTT)\n");
-            g_net_state.flag = 1;
-        }
+        iot_mqtt_handle_sock_int(socketid, intstat);
         return;
     }
     
diff --git a/vd960DBN/BLE/OnlyUpdateApp_Peripheral/APP/peripheral_main.c b/vd960DBN/BLE/OnlyUpdateApp_Peripheral/APP/peripheral_main.c
index 0e09359..796f827 100644
--- a/vd960DBN/BLE/OnlyUpdateApp_Peripheral/APP/peripheral_main.c
+++ b/vd960DBN/BLE/OnlyUpdateApp_Peripheral/APP/peripheral_main.c
@@ -271,7 +271,7 @@ void Main_Circulation(void)
 
         if (g_sub_code_enable.iot_enable) {
             iot_mqtt_publish_sensor();  // Push 0xC0 sensor data to MQTT broker
-            poll_mqtt();                // MQTT PINGREQ heartbeat (in net_srv.c)
+            iot_mqtt_poll();            // IoT MQTT state machine + PINGREQ keepalive
         } else {
             tcp_json_push_sensor();     // Push 0xC0 sensor data to TCP JSON client
             tcp_json_poll();