diff --git a/examples/tencent_firmware_mqtt/tencent_firmware_mqtt.c b/examples/tencent_firmware_mqtt/tencent_firmware_mqtt.c
index e204cb4f..62be865f 100644
--- a/examples/tencent_firmware_mqtt/tencent_firmware_mqtt.c
+++ b/examples/tencent_firmware_mqtt/tencent_firmware_mqtt.c
@@ -13,6 +13,7 @@ void mqtt_demo_task(void)
     char *key = "ttOARy0PjYgzd9OSs4Z3RA==";
 
     device_info_t dev_info;
+    memset(&dev_info, 0, sizeof(device_info_t));
 
     esp8266_tencent_firmware_sal_init(HAL_UART_PORT_3);
     esp8266_tencent_firmware_join_ap("SheldonDai", "srnr6x9xbhmb0");