diff --git a/pages/annex/auth/index.vue b/pages/annex/auth/index.vue
index be7b553..d21c33a 100644
--- a/pages/annex/auth/index.vue
+++ b/pages/annex/auth/index.vue
@@ -78,6 +78,15 @@
 		return '';
 	}
 
+	/* unionid：用户中心身份键（预留功能）。小程序登录态静默缓存（store/Cache 'UNIONID'）；
+	   带上后 box_app 授权成功自动推送用户中心并回写 openid→unionid 映射。 */
+	function getUnionid() {
+		let uid = store.state.app.unionid;
+		if (uid) return uid;
+		try { uid = uni.getStorageSync('UNIONID'); } catch (e) {}
+		return uid || '';
+	}
+
 	export default {
 		data() {
 			return {
@@ -141,7 +150,11 @@
 				}
 				const openid = getOpenid() || this.openid;
 				if (!openid) return uni.showToast({ title: '未获得 openid，请先登录', icon: 'none' });
+				/* unionid：用户中心身份键（预留）。带上后 box_app 授权成功自动推送用户中心
+				   并回写 openid→unionid 映射；没拿到也不影响授权（后端可映射兜底）。 */
+				const unionid = getUnionid();
 				const api = 'https://mp.yizhezhe.com/api/mp/public/auth/profile?openid=' + encodeURIComponent(openid) +
+					(unionid ? '&unionid=' + encodeURIComponent(unionid) : '') +
 					(this._authCode ? '&code=' + encodeURIComponent(this._authCode) : '') +
 					(this.authNickname ? '&nickname=' + encodeURIComponent(this.authNickname) : '') +
 					(this.authAvatar ? '&avatar=' + encodeURIComponent(this.authAvatar) : '');