diff --git a/components/lwip/port/esp8266/netif/ethernetif.c b/components/lwip/port/esp8266/netif/ethernetif.c
index 1c3edf90..42dbef09 100644
--- a/components/lwip/port/esp8266/netif/ethernetif.c
+++ b/components/lwip/port/esp8266/netif/ethernetif.c
@@ -238,7 +238,9 @@ static int low_level_send_cb(esp_aio_t* aio)
 
     pbuf_free(pbuf);
 
+#if ESP_UDP
     udp_sync_trigger();
+#endif
 
     return 0;
 }