diff --git a/frontend/app/web-gold/src/views/kling/stores/useDigitalHumanStore.ts b/frontend/app/web-gold/src/views/kling/stores/useDigitalHumanStore.ts
index 8ed6d3ad25..ad06fe3114 100644
--- a/frontend/app/web-gold/src/views/kling/stores/useDigitalHumanStore.ts
+++ b/frontend/app/web-gold/src/views/kling/stores/useDigitalHumanStore.ts
@@ -17,6 +17,11 @@ import { useUpload } from '@/composables/useUpload'
 import { DEFAULT_VOICE_PROVIDER } from '@/config/voiceConfig'
 import type { VoiceMeta, Video, PipelinePhase, VideoStep, AudioStep, CreateStep, TimelineData } from '../types/identify-face'
 
+// ========== 常量 ==========
+
+/** 视频文件大小上限 100MB（302.ai Kling 接口限制） */
+const MAX_VIDEO_SIZE = 100 * 1024 * 1024
+
 // ========== 内部类型定义 ==========
 
 /** 音频数据 */
@@ -235,6 +240,11 @@ export const useDigitalHumanStore = defineStore('digitalHuman', () => {
       return
     }
 
+    if (file.size > MAX_VIDEO_SIZE) {
+      toast.error('视频文件不能超过 100MB')
+      return
+    }
+
     // 释放旧的 blob URL
     if (videoPreviewUrl.value?.startsWith('blob:')) {
       URL.revokeObjectURL(videoPreviewUrl.value)
@@ -251,6 +261,12 @@ export const useDigitalHumanStore = defineStore('digitalHuman', () => {
 
   /** 从素材库选择视频（选择后自动识别） */
   async function selectVideo(video: Video) {
+    // 校验视频大小
+    if (video.fileSize && video.fileSize > MAX_VIDEO_SIZE) {
+      toast.error('视频文件不能超过 100MB')
+      return
+    }
+
     selectedVideo.value = video
     videoFile.value = null
     videoSource.value = 'select'