diff --git a/mixly/common/modules/mixly-modules/web-socket/burn-upload.js b/mixly/common/modules/mixly-modules/web-socket/burn-upload.js
index d6937575..4c94cb52 100644
--- a/mixly/common/modules/mixly-modules/web-socket/burn-upload.js
+++ b/mixly/common/modules/mixly-modules/web-socket/burn-upload.js
@@ -31,8 +31,8 @@ goog.loadJs('web', () => {
 
     const { SELECTED_BOARD, BOARD } = Config;
 
-    // 引入本地 Web.BU 模块，用于 MicroPython 本地上传
-    const WebBU = Mixly.Web?.BU;
+    // WebBU 需要在使用时动态获取，避免模块加载顺序问题
+    const getWebBU = () => Mixly.Web?.BU;
 
     const { Serial } = WebSocket;
 
@@ -74,6 +74,7 @@ goog.loadJs('web', () => {
 
             this.initBurn = function () {
                 // MicroPython 板卡使用本地 Web Serial API 烧录，而非通过服务器
+                const WebBU = getWebBU();
                 if (SELECTED_BOARD?.language === 'MicroPython' && WebBU) {
                     return WebBU.initBurn();
                 }
@@ -111,6 +112,7 @@ goog.loadJs('web', () => {
 
             this.initUpload = function () {
                 // MicroPython 板卡使用本地 Web Serial API 上传，而非通过服务器
+                const WebBU = getWebBU();
                 if (SELECTED_BOARD?.language === 'MicroPython' && WebBU) {
                     return WebBU.initUpload();
                 }