diff --git a/apps/web/src/pages/generate/GeneratePage.tsx b/apps/web/src/pages/generate/GeneratePage.tsx
index 1e387083f..ec232cfc1 100644
--- a/apps/web/src/pages/generate/GeneratePage.tsx
+++ b/apps/web/src/pages/generate/GeneratePage.tsx
@@ -1,21 +1,20 @@
 /**
- * 智能剪辑页面 — V24 前端预览播放器架构改造
+ * 智能剪辑页面 — 服务器渲染预览架构
  * 7 步向导：选择模板 → 素材 → 配音 → 标题 → 预览 → 封面 → 确认生成
  * 左右布局：左侧 generate-form + 右侧 generate-preview
  *
- * 架构改造：
- * - Step5 预览改为前端素材切片播放（FrontendPreviewPlayer）
- * - 完全去除后端 FFmpeg 预览依赖
- * - 标题样式通过 CSS 层实时叠加，所见即所得
- * - 最终成片仍走后端 FFmpeg 渲染（Step7 确认生成）
+ * 架构：
+ * - Step4+ 右侧预览面板自动创建服务器预览渲染任务（POST /generation/preview）
+ * - 轮询完成后播放服务器渲染的真实视频（<video> 标签）
+ * - 标题样式编辑时 CSS 层实时叠加预览
+ * - 素材/配音/BGM 变更自动重新渲染；标题变更标记 stale
+ * - 点"确认生成"时走 confirm 路径，成品就是预览视频本身，100% 一致
  */
-import React, { useMemo } from "react"
+import React, { useMemo, useCallback } from "react"
 import { Modal, message } from "antd"
 import { useNavigate } from "react-router-dom"
 import type { VoiceClone } from "@/api/voice-clone"
-import { useQuery } from "@tanstack/react-query"
 import { useCloneProgress } from "@/hooks/useCloneProgress"
-import { getAssetsByKind } from "@/api/assets"
 import CloneModal from "@/components/voice/CloneModal"
 import GenerateHeader from "./components/GenerateHeader"
 import {
@@ -31,6 +30,7 @@ import { useGenerateFormState } from "./hooks/useGenerateFormState"
 import { useStepNavigation } from "./hooks/useStepNavigation"
 import { useGenerateVideo } from "./hooks/useGenerateVideo"
 import { usePreviewAssets } from "./hooks/usePreviewAssets"
+import { useServerPreview } from "./hooks/useServerPreview"
 import { useTitleStyleUpdaters } from "./hooks/useStep4Title/useTitleStyleUpdaters"
 import "./generate.css"
 
@@ -83,7 +83,7 @@ const GeneratePage: React.FC = () => {
     setStoredSourceEditPlanId,
   } = formState
 
-  /* ── 标题样式回调（Step5 样式面板 + 右侧预览 CSS 层共用） ── */
+  /* ── 标题样式回调 ── */
   const styleUpdaters = useTitleStyleUpdaters({
     titleSettings,
     onTitleSettingsChange: setTitleSettings,
@@ -98,30 +98,19 @@ const GeneratePage: React.FC = () => {
     message.success("音色克隆成功！")
   }
 
-  /* ── 前端预览：加载选中素材的视频文件信息 ── */
+  /* ── 素材 ID 列表 ── */
   const previewAssetIds = useMemo(
     () => (materialMode === "auto" ? smartSelectedIds : selectedMaterials),
     [materialMode, smartSelectedIds, selectedMaterials],
   )
-  // previewTaskId 不再因设置变化而自动清除。
-  // 用户修改设置后，confirmGeneration 会检测参数是否匹配：
-  // 匹配则复用产物秒出；不匹配则后端自动 fallback 到 createGenerationTask 重新渲染。
-  // 只有当用户明确返回 Step5 重新预览时，才会创建新的预览任务并覆盖 previewTaskId。
 
-  const previewAssetsEnabled = currentStep >= 4 && previewAssetIds.length > 0
-  const {
-    assets: previewAssets,
-    loading: previewAssetsLoading,
-    ready: previewAssetsReady,
-  } = usePreviewAssets(previewAssetIds, previewAssetsEnabled)
-
-  /* ── 当前模板对象（传给前端预览播放器） ── */
+  /* ── 当前模板对象 ── */
   const currentTemplate = useMemo(
     () => userTemplates.find((t) => t.id === selectedTemplate) || null,
     [userTemplates, selectedTemplate],
   )
 
-  /* ── BGM 配置：从当前模板读取，受 bgm 开关控制 ── */
+  /* ── BGM 配置 ── */
   const bgmConfig = useMemo(
     () => ({
       enabled: bgm,
@@ -130,27 +119,82 @@ const GeneratePage: React.FC = () => {
     [bgm, currentTemplate],
   )
 
-  /* ── 视频总时长计算（用于配音时长校验） ── */
+  /* ── 加载素材详情（仅用于配音时长校验，不用于播放） ── */
+  const previewAssetsEnabled = previewAssetIds.length > 0
+  const { assets: previewAssets } = usePreviewAssets(previewAssetIds, previewAssetsEnabled)
+
+  /* ── 视频总时长计算 ── */
   const totalVideoDuration = useMemo(() => {
-    // 优先用素材精确时长；素材未加载时用模板 segments 的 duration_max 之和估算
     const exact = calculateTotalVideoDuration(previewAssets, currentTemplate ?? undefined)
     if (exact > 0) return exact
     return estimateTotalVideoDuration(currentTemplate ?? undefined)
   }, [previewAssets, currentTemplate])
 
-  /* ── 配音音频 URL ── */
-  const { data: voiceMaterials = [] } = useQuery({
-    queryKey: ["assets", "voice"],
-    queryFn: () => getAssetsByKind("voice", { limit: 50 }),
+  /* ── 解析配音 ID ── */
+  const voiceLibraryId = useMemo(
+    () => (voiceMode === "clone" ? selectedClonedVoice || "" : selectedVoice || ""),
+    [voiceMode, selectedClonedVoice, selectedVoice],
+  )
+
+  /* ── 构建服务器预览请求参数 ── */
+  const buildPreviewRequest = useCallback(() => {
+    return {
+      template_id: selectedTemplate,
+      asset_ids: previewAssetIds,
+      duration: duration || 30,
+      video_ratio: videoRatio,
+      ...(voiceLibraryId ? { voice_library_id: voiceLibraryId } : {}),
+      bgm_config: {
+        enabled: bgm !== false,
+        ...(bgmConfig.music_id ? { preset_id: bgmConfig.music_id } : {}),
+      },
+      ...(titleSettings.title
+        ? {
+            title_config: {
+              text: titleSettings.title,
+              font: titleSettings.font,
+              font_size: titleSettings.size,
+              font_color: titleSettings.color,
+              position: titleSettings.position,
+              bold: titleSettings.bold,
+              stroke: titleSettings.stroke,
+              shadow: titleSettings.shadow,
+            },
+          }
+        : {}),
+    }
+  }, [
+    selectedTemplate,
+    previewAssetIds,
+    duration,
+    videoRatio,
+    voiceLibraryId,
+    bgm,
+    bgmConfig,
+    titleSettings,
+  ])
+
+  /* ── 服务器预览 ── */
+  const serverPreviewEnabled = currentStep >= 4 && !!selectedTemplate && previewAssetIds.length > 0
+
+  const {
+    status: previewStatus,
+    videoUrl: previewVideoUrl,
+    progress: previewProgress,
+    error: previewError,
+    triggerPreview,
+  } = useServerPreview({
+    enabled: serverPreviewEnabled,
+    buildRequest: buildPreviewRequest,
+    onPreviewTaskCreated: (taskId, planId) => {
+      setPreviewTaskId(taskId)
+      if (planId) setStoredSourceEditPlanId(planId)
+    },
   })
 
-  const voiceAudioUrl = useMemo(() => {
-    if (!selectedVoice) return undefined
-    const asset = voiceMaterials.find((v) => v.id === selectedVoice)
-    return asset?.file_url || undefined
-  }, [selectedVoice, voiceMaterials])
-
   /* ── 步骤导航 ── */
+  // Step5 需要服务器预览完成才能前进
+  const previewReady = previewStatus === "ready"
   const { goNext, goPrev } = useStepNavigation({
     currentStep,
     setCurrentStep,
@@ -159,7 +203,7 @@ const GeneratePage: React.FC = () => {
     selectedMaterials,
     smartSelectedIds,
     titleSettings,
-    previewReady: previewAssetsReady,
+    previewReady,
   })
 
   /* ── 视频生成核心逻辑 ── */
@@ -199,19 +243,21 @@ const GeneratePage: React.FC = () => {
     },
   })
 
+  /* ── 手动重新预览（标题变更后或失败重试） ── */
+  const handleRetryPreview = useCallback(() => {
+    triggerPreview()
+  }, [triggerPreview])
+
   /* ================================================================
-     渲染 — 主页面
+     渲染
      ================================================================ */
 
   return (
     <div className="xx-generate-page">
-      {/* ── 页头 ── */}
       <GenerateHeader fromEditPlan={!!editPlanId} />
 
-      {/* ── 步骤条 ── */}
       <GenerateStepsBar currentStep={currentStep} onStepClick={setCurrentStep} />
 
-      {/* ── 主布局 ── */}
       <div className="xx-generate-layout">
         {/* ════ 左侧：表单区 ════ */}
         <div className="xx-generate-form">
@@ -228,7 +274,6 @@ const GeneratePage: React.FC = () => {
             onSmartSelectedIdsChange={setSmartSelectedIds}
             titleSettings={titleSettings}
             onTitleSettingsChange={setTitleSettings}
-            /* 标题样式回调 */
             onUpdatePosition={styleUpdaters.updatePosition}
             onUpdateFont={styleUpdaters.updateFont}
             onUpdateSize={styleUpdaters.updateSize}
@@ -268,6 +313,8 @@ const GeneratePage: React.FC = () => {
             onRetry={handleRetryGenerate}
             onDismissError={handleDismissError}
             presetVoices={presetVoices}
+            previewStatus={previewStatus}
+            onRetryPreview={handleRetryPreview}
           />
 
           <GenerateStepActions
@@ -281,18 +328,18 @@ const GeneratePage: React.FC = () => {
           />
         </div>
 
-        {/* ════ 右侧：预览 + 生成结果 ════ */}
+        {/* ════ 右侧：预览 + 结果 ════ */}
         <div className="xx-generate-right-col">
-          {/* 预览视频面板（Step4+ 显示，含 CSS 标题实时预览层） */}
           {currentStep >= 4 && (
             <PreviewVideoPanel
-              assets={previewAssets}
-              template={currentTemplate}
+              previewStatus={previewStatus}
+              videoUrl={previewVideoUrl}
+              progress={previewProgress}
+              error={previewError}
+              onRetry={handleRetryPreview}
               videoRatio={videoRatio}
-              assetsReady={previewAssetsReady}
-              assetsLoading={previewAssetsLoading}
               titleSettings={titleSettings}
-              voiceAudioUrl={voiceAudioUrl}
+              assetCount={previewAssetIds.length}
             />
           )}
           {currentStep >= 6 && (
@@ -314,7 +361,7 @@ const GeneratePage: React.FC = () => {
         </div>
       </div>
 
-      {/* ── 视频预览弹窗 ── */}
+      {/* 视频预览弹窗 */}
       <Modal
         className="xx-preview-modal"
         open={previewModalOpen}
@@ -337,7 +384,7 @@ const GeneratePage: React.FC = () => {
         )}
       </Modal>
 
-      {/* ── 音色克隆弹窗 ── */}
+      {/* 音色克隆弹窗 */}
       <CloneModal
         open={cloneModalOpen}
         onClose={() => setCloneModalOpen(false)}
diff --git a/apps/web/src/pages/generate/components/GenerateStepContent.tsx b/apps/web/src/pages/generate/components/GenerateStepContent.tsx
index de363c464..fc08f6ba6 100644
--- a/apps/web/src/pages/generate/components/GenerateStepContent.tsx
+++ b/apps/web/src/pages/generate/components/GenerateStepContent.tsx
@@ -84,6 +84,10 @@ export interface GenerateStepContentProps {
   bgm: boolean
   /** BGM 配置（来自模板） */
   bgmConfig?: { enabled: boolean; music_id?: string }
+  /** 服务器预览状态 */
+  previewStatus?: import("../hooks/useServerPreview").ServerPreviewStatus
+  /** 重新预览回调 */
+  onRetryPreview?: () => void
 }
 
 export const GenerateStepContent: React.FC<GenerateStepContentProps> = (props) => {
@@ -133,6 +137,8 @@ export const GenerateStepContent: React.FC<GenerateStepContentProps> = (props) =
     onSourceEditPlanIdExtracted,
     bgm,
     bgmConfig,
+    previewStatus,
+    onRetryPreview,
   } = props
 
   /* 当前模板的 segments，传给 Step2 构建 clips */
@@ -191,6 +197,8 @@ export const GenerateStepContent: React.FC<GenerateStepContentProps> = (props) =
           onApplyPreset={onApplyPreset}
           activePreset={activePreset}
           titlePresets={titlePresets}
+          previewStatus={previewStatus || "idle"}
+          onRetryPreview={onRetryPreview || (() => {})}
         />
       )
     case 6:
diff --git a/apps/web/src/pages/generate/components/PreviewVideoPanel.tsx b/apps/web/src/pages/generate/components/PreviewVideoPanel.tsx
index ee03f16b5..28745a5e7 100644
--- a/apps/web/src/pages/generate/components/PreviewVideoPanel.tsx
+++ b/apps/web/src/pages/generate/components/PreviewVideoPanel.tsx
@@ -1,39 +1,42 @@
 /**
- * 右侧预览视频面板
- * Step4+: 显示预览视频面板
- * Step5: 前端实时预览 — 用原生 video 播放素材片段 + CSS 标题叠加
+ * 右侧预览视频面板 — 服务器渲染预览架构
  *
- * 架构改造：完全去除后端 FFmpeg 预览依赖
- * - 使用 FrontendPreviewPlayer 直接播放素材片段
- * - TitleOverlay CSS 层实时响应标题样式变化
+ * Step4+: 显示预览面板
+ * Step5: 播放服务器渲染的真实视频（POST /generation/preview）
  *
- * 布局：本组件提供 .xx-preview-video 容器（position: relative + overflow: hidden）
- * FrontendPreviewPlayer 的内容通过 absolute 定位填充容器
- * TitleOverlay 通过 absolute 定位 + z-index: 30 覆盖在最上层
+ * 架构：
+ * - 进入 Step4/5 时自动创建服务器预览渲染任务
+ * - 轮询完成后用 <video> 标签播放返回的 video_url
+ * - 标题样式编辑时 CSS TitleOverlay 实时叠加预览
+ * - 素材/配音/BGM 变更自动重新渲染
+ * - 标题文字/样式变更标记 stale，保留旧视频 + 显示"重新预览"按钮
+ *
+ * 点"确认生成"时走 confirm 路径，成品就是预览视频本身，100% 一致。
  */
 import React, { useMemo, useRef, useState, useEffect } from "react"
-import { LoadingOutlined } from "@ant-design/icons"
-import type { AssetItem } from "@/api/assets"
-import type { EditingTemplate } from "@/api/editing-planner"
+import { LoadingOutlined, ReloadOutlined, ExclamationCircleOutlined } from "@ant-design/icons"
+import { Button } from "antd"
 import type { TitleSettings } from "../types"
 import { getFontFamily } from "../constants"
-import FrontendPreviewPlayer from "./FrontendPreviewPlayer"
+import type { ServerPreviewStatus } from "../hooks/useServerPreview"
 
 interface PreviewVideoPanelProps {
-  /** 已加载的素材列表 */
-  assets: AssetItem[]
-  /** 当前模板 */
-  template: EditingTemplate | null
+  /** 服务器预览状态 */
+  previewStatus: ServerPreviewStatus
+  /** 服务器渲染视频 URL */
+  videoUrl: string | null
+  /** 渲染进度 0-100 */
+  progress: number
+  /** 错误信息 */
+  error: string | null
+  /** 重新预览回调 */
+  onRetry: () => void
   /** 视频比例 */
   videoRatio: string
-  /** 素材是否已加载就绪 */
-  assetsReady: boolean
-  /** 素材是否正在加载 */
-  assetsLoading: boolean
-  /** 标题设置 — 用于 CSS 实时预览层 */
+  /** 标题设置 — CSS 实时预览层 */
   titleSettings?: TitleSettings
-  /** 配音音频 URL */
-  voiceAudioUrl?: string
+  /** 素材数量 */
+  assetCount?: number
 }
 
 /* ── ASS 坐标系参数（与后端 ass_subtitle_builder.py 一致） ── */
@@ -42,13 +45,8 @@ const ASS_TITLE_MARGIN_TOP = 60
 const ASS_TITLE_MARGIN_BOTTOM = 60
 const ASS_TITLE_MARGIN_SIDE = 40
 
-/**
- * 根据 position 计算 CSS 垂直定位
- * 与后端 position_to_ass_alignment() 对齐：top→8, center→5, bottom→2
- */
 function getPositionStyle(position: string): React.CSSProperties {
   const sidePercent = (ASS_TITLE_MARGIN_SIDE / 1280) * 100
-
   switch (position) {
     case "bottom":
       return {
@@ -76,16 +74,11 @@ function getPositionStyle(position: string): React.CSSProperties {
   }
 }
 
-/**
- * 构建 CSS 标题层的样式
- * 所有渲染参数与后端 FFmpeg ASS 字幕一致
- */
 function buildTitleStyle(settings: TitleSettings, containerHeight: number): React.CSSProperties {
-  // 用 px 计算 fontSize，不再依赖父元素 font-size 的百分比
   const fontSizePx =
     containerHeight > 0
       ? (Math.min(settings.size, 96) / ASS_VIDEO_HEIGHT) * containerHeight
-      : (Math.min(settings.size, 96) / ASS_VIDEO_HEIGHT) * 400 // fallback
+      : (Math.min(settings.size, 96) / ASS_VIDEO_HEIGHT) * 400
 
   const base: React.CSSProperties = {
     fontFamily: getFontFamily(settings.font),
@@ -100,28 +93,16 @@ function buildTitleStyle(settings: TitleSettings, containerHeight: number): Reac
     paddingLeft: `${(ASS_TITLE_MARGIN_SIDE / 1280) * 100}%`,
     paddingRight: `${(ASS_TITLE_MARGIN_SIDE / 1280) * 100}%`,
   }
-
-  if (settings.stroke) {
-    base.WebkitTextStroke = "1px #000000"
-  }
-
-  if (settings.shadow) {
-    base.textShadow = "2px 2px 4px rgba(0,0,0,0.8)"
-  }
-
+  if (settings.stroke) base.WebkitTextStroke = "1px #000000"
+  if (settings.shadow) base.textShadow = "2px 2px 4px rgba(0,0,0,0.8)"
   return base
 }
 
-/**
- * CSS 标题预览覆盖层
- * 始终渲染：有标题显示标题，无标题显示占位文本"标题预览"
- * z-index: 20（在视频 z-index:1 和控制条 z-index:10 之上）
- */
+/** CSS 标题实时预览覆盖层 */
 const TitleOverlay: React.FC<{ titleSettings: TitleSettings }> = ({ titleSettings }) => {
   const containerRef = useRef<HTMLDivElement>(null)
-  const [containerHeight, setContainerHeight] = useState(400) // fallback
+  const [containerHeight, setContainerHeight] = useState(400)
 
-  // ResizeObserver 获取容器实际高度
   useEffect(() => {
     const el = containerRef.current
     if (!el) return
@@ -132,7 +113,6 @@ const TitleOverlay: React.FC<{ titleSettings: TitleSettings }> = ({ titleSetting
       }
     })
     ro.observe(el)
-    // 初始化也读一次
     const rect = el.getBoundingClientRect()
     if (rect.height > 0) setContainerHeight(rect.height)
     return () => ro.disconnect()
@@ -144,7 +124,7 @@ const TitleOverlay: React.FC<{ titleSettings: TitleSettings }> = ({ titleSetting
   )
   const titleStyle = useMemo(
     () => buildTitleStyle(titleSettings, containerHeight),
-    // eslint-disable-next-line react-hooks/exhaustive-deps -- 已逐字段列出 titleSettings 依赖
+    // eslint-disable-next-line react-hooks/exhaustive-deps
     [
       containerHeight,
       titleSettings.font,
@@ -170,13 +150,7 @@ const TitleOverlay: React.FC<{ titleSettings: TitleSettings }> = ({ titleSetting
         overflow: "hidden",
       }}
     >
-      <div
-        style={{
-          ...positionStyle,
-          ...titleStyle,
-          position: "absolute",
-        }}
-      >
+      <div style={{ ...positionStyle, ...titleStyle, position: "absolute" }}>
         {displayTitle.split("/").map((part, i) => (
           <span key={i}>
             {i > 0 && <br />}
@@ -191,30 +165,47 @@ const TitleOverlay: React.FC<{ titleSettings: TitleSettings }> = ({ titleSetting
 /* ── 主组件 ── */
 
 export const PreviewVideoPanel: React.FC<PreviewVideoPanelProps> = ({
-  assets,
-  template,
+  previewStatus,
+  videoUrl,
+  progress,
+  error,
+  onRetry,
   videoRatio,
-  assetsReady,
-  assetsLoading,
   titleSettings,
-  voiceAudioUrl,
+  assetCount,
 }) => {
   const videoAspectStyle = { aspectRatio: (videoRatio || "9:16").replace(":", "/") }
+  const isLoading = previewStatus === "loading"
+  const isReady = previewStatus === "ready" || previewStatus === "stale"
+  const isFailed = previewStatus === "failed"
+  const isIdle = previewStatus === "idle"
+  const isStale = previewStatus === "stale"
 
   return (
     <div className="xx-generate-preview">
       <div className="xx-preview-header">
         <h3>预览视频</h3>
-        {assetsReady && assets.length > 0 && <span className="xx-preview-badge">实时预览</span>}
+        {isReady && !isStale && <span className="xx-preview-badge">服务器渲染</span>}
+        {isStale && (
+          <span
+            style={{
+              fontSize: 12,
+              color: "#faad14",
+              display: "flex",
+              alignItems: "center",
+              gap: 4,
+            }}
+          >
+            <ExclamationCircleOutlined /> 配置已变更
+          </span>
+        )}
+        {isLoading && <span className="xx-preview-badge">渲染中</span>}
       </div>
 
-      {/* ✅ 预览容器 — 唯一的 .xx-preview-video 容器
-          内部所有内容（视频、控制条、标题叠加层）通过 absolute 定位填充 */}
       <div className="xx-preview-video" style={{ ...videoAspectStyle, position: "relative" }}>
-        {/* 加载中状态 */}
-        {assetsLoading && (
+        {/* 加载中 */}
+        {isLoading && (
           <div
-            className="xx-preview-loading-center"
             style={{
               position: "absolute",
               inset: 0,
@@ -223,34 +214,130 @@ export const PreviewVideoPanel: React.FC<PreviewVideoPanelProps> = ({
               alignItems: "center",
               justifyContent: "center",
               zIndex: 5,
+              background: "rgba(0,0,0,0.6)",
             }}
           >
             <LoadingOutlined style={{ fontSize: 36, color: "#fff" }} spin />
-            <p style={{ marginTop: 12, color: "rgba(255,255,255,0.8)", fontSize: 14 }}>
-              加载素材中...
+            <p style={{ marginTop: 12, color: "rgba(255,255,255,0.9)", fontSize: 14 }}>
+              正在渲染预览视频{progress > 0 ? `...${progress}%` : "..."}
+            </p>
+            <p style={{ marginTop: 4, color: "rgba(255,255,255,0.5)", fontSize: 12 }}>
+              首次渲染约需 30-60 秒
             </p>
           </div>
         )}
 
-        {/* 前端播放器（视频 + 控制条 + 播放按钮）*/}
-        <FrontendPreviewPlayer
-          assets={assets}
-          template={template}
-          videoRatio={videoRatio}
-          ready={assetsReady}
-          voiceAudioUrl={voiceAudioUrl}
-        />
+        {/* 空闲状态（尚未触发预览） */}
+        {isIdle && (
+          <div
+            style={{
+              position: "absolute",
+              inset: 0,
+              display: "flex",
+              flexDirection: "column",
+              alignItems: "center",
+              justifyContent: "center",
+              background: "rgba(0,0,0,0.3)",
+              zIndex: 5,
+            }}
+          >
+            <p style={{ color: "rgba(255,255,255,0.7)", fontSize: 14 }}>等待素材选择...</p>
+          </div>
+        )}
 
-        {/* CSS 标题实时预览层 — z-index: 20，始终渲染在内容层之上 */}
-        {titleSettings && <TitleOverlay titleSettings={titleSettings} />}
+        {/* 服务器渲染的真实视频 */}
+        {isReady && videoUrl && (
+          <video
+            key={videoUrl}
+            src={videoUrl}
+            controls
+            autoPlay
+            loop
+            playsInline
+            style={{
+              width: "100%",
+              height: "100%",
+              objectFit: "contain",
+              position: "absolute",
+              inset: 0,
+              zIndex: 1,
+            }}
+          />
+        )}
+
+        {/* 标题样式实时预览层（仅在有视频时叠加） */}
+        {isReady && titleSettings && <TitleOverlay titleSettings={titleSettings} />}
+
+        {/* stale 遮罩：配置变更提示 */}
+        {isStale && (
+          <div
+            style={{
+              position: "absolute",
+              bottom: 0,
+              left: 0,
+              right: 0,
+              padding: "10px 16px",
+              background: "linear-gradient(transparent, rgba(0,0,0,0.85))",
+              display: "flex",
+              alignItems: "center",
+              justifyContent: "space-between",
+              gap: 8,
+              zIndex: 30,
+            }}
+          >
+            <span style={{ color: "rgba(255,255,255,0.9)", fontSize: 12 }}>
+              配置已变更，预览内容可能不是最新
+            </span>
+            <Button size="small" type="primary" icon={<ReloadOutlined />} onClick={onRetry}>
+              重新预览
+            </Button>
+          </div>
+        )}
+
+        {/* 错误状态 */}
+        {isFailed && (
+          <div
+            style={{
+              position: "absolute",
+              inset: 0,
+              display: "flex",
+              flexDirection: "column",
+              alignItems: "center",
+              justifyContent: "center",
+              background: "rgba(0,0,0,0.7)",
+              zIndex: 10,
+              padding: 24,
+            }}
+          >
+            <ExclamationCircleOutlined style={{ fontSize: 40, color: "#ff4d4f" }} />
+            <p
+              style={{
+                marginTop: 12,
+                color: "rgba(255,255,255,0.9)",
+                fontSize: 14,
+                textAlign: "center",
+              }}
+            >
+              {error || "预览渲染失败"}
+            </p>
+            <Button
+              type="primary"
+              icon={<ReloadOutlined />}
+              onClick={onRetry}
+              style={{ marginTop: 12 }}
+            >
+              重新预览
+            </Button>
+          </div>
+        )}
       </div>
 
       {/* 素材信息 */}
-      {assetsReady && assets.length > 0 && (
+      {assetCount !== undefined && assetCount > 0 && (
         <div className="xx-preview-info">
           <div className="xx-preview-info-row">
             <span>素材数</span>
-            <span>{assets.length} 个</span>
+            <span>{assetCount} 个</span>
           </div>
           <div className="xx-preview-info-row">
             <span>比例</span>
diff --git a/apps/web/src/pages/generate/components/Step5GeneratePreview.tsx b/apps/web/src/pages/generate/components/Step5GeneratePreview.tsx
index 19dd51656..2c327facc 100644
--- a/apps/web/src/pages/generate/components/Step5GeneratePreview.tsx
+++ b/apps/web/src/pages/generate/components/Step5GeneratePreview.tsx
@@ -1,16 +1,21 @@
 /**
- * Step 5 生成预览组件
- * 架构改造：移除后端预览生成，改为前端实时预览
- * 左侧仅保留标题样式面板，视频在右侧 PreviewVideoPanel 实时播放
+ * Step 5 预览设置组件
+ *
+ * 服务器渲染预览架构：
+ * - 进入此步骤时右侧面板自动播放服务器渲染的真实视频
+ * - 标题样式可实时调整（CSS 层叠加预览）
+ * - 调整标题后点击"重新预览"可刷新服务器渲染结果
+ * - 素材/配音/BGM 变更会自动重新渲染
  */
 import React from "react"
-import { PlayCircleOutlined } from "@ant-design/icons"
+import { PlayCircleOutlined, ReloadOutlined } from "@ant-design/icons"
+import { Button } from "antd"
 import { POSITION_OPTIONS, FONT_OPTIONS } from "../constants"
 import type { TitleSettings } from "../types"
+import type { ServerPreviewStatus } from "../hooks/useServerPreview"
 import TitleStylePanel from "./title/TitleStylePanel"
 
 interface Step5GeneratePreviewProps {
-  /* 标题样式 */
   titleSettings: TitleSettings
   onUpdatePosition: (position: string) => void
   onUpdateFont: (font: string) => void
@@ -22,6 +27,10 @@ interface Step5GeneratePreviewProps {
   onApplyPreset: (presetKey: string) => void
   activePreset: string | null
   titlePresets: { key: string; label: string; previewStyle: React.CSSProperties }[]
+  /** 服务器预览状态 */
+  previewStatus: ServerPreviewStatus
+  /** 重新预览回调 */
+  onRetryPreview: () => void
 }
 
 const Step5GeneratePreview: React.FC<Step5GeneratePreviewProps> = ({
@@ -36,14 +45,18 @@ const Step5GeneratePreview: React.FC<Step5GeneratePreviewProps> = ({
   onApplyPreset,
   activePreset,
   titlePresets,
+  previewStatus,
+  onRetryPreview,
 }) => {
+  const isLoading = previewStatus === "loading"
+  const isStale = previewStatus === "stale"
+  const isFailed = previewStatus === "failed"
+
   return (
     <div className="xx-form-section">
       <h3>🎬 预览设置</h3>
 
-      {/* 前端实时预览提示 */}
       <div
-        className="xx-preview-tip"
         style={{
           display: "flex",
           alignItems: "center",
@@ -57,11 +70,71 @@ const Step5GeneratePreview: React.FC<Step5GeneratePreviewProps> = ({
       >
         <PlayCircleOutlined style={{ fontSize: 18, color: "#3b82f6" }} />
         <span style={{ fontSize: 13, color: "var(--text-secondary, #666)" }}>
-          右侧面板直接播放素材片段，调整标题样式可实时预览效果
+          右侧为服务器渲染的真实预览视频，最终成片与预览完全一致
         </span>
       </div>
 
-      {/* 标题样式面板 */}
+      {/* 配置变更提示条 */}
+      {isStale && (
+        <div
+          style={{
+            display: "flex",
+            alignItems: "center",
+            justifyContent: "space-between",
+            gap: 8,
+            padding: "10px 16px",
+            background: "rgba(250, 173, 20, 0.1)",
+            borderRadius: 8,
+            marginBottom: 16,
+            border: "1px solid rgba(250, 173, 20, 0.2)",
+          }}
+        >
+          <span style={{ fontSize: 13, color: "#d48806" }}>
+            标题已修改，点击重新预览刷新服务器渲染
+          </span>
+          <Button size="small" type="primary" icon={<ReloadOutlined />} onClick={onRetryPreview}>
+            重新预览
+          </Button>
+        </div>
+      )}
+
+      {isFailed && (
+        <div
+          style={{
+            display: "flex",
+            alignItems: "center",
+            justifyContent: "space-between",
+            gap: 8,
+            padding: "10px 16px",
+            background: "rgba(255, 77, 79, 0.1)",
+            borderRadius: 8,
+            marginBottom: 16,
+            border: "1px solid rgba(255, 77, 79, 0.2)",
+          }}
+        >
+          <span style={{ fontSize: 13, color: "#ff4d4f" }}>预览渲染失败</span>
+          <Button size="small" danger icon={<ReloadOutlined />} onClick={onRetryPreview}>
+            重新预览
+          </Button>
+        </div>
+      )}
+
+      {isLoading && (
+        <div
+          style={{
+            padding: "10px 16px",
+            background: "rgba(82, 196, 26, 0.08)",
+            borderRadius: 8,
+            marginBottom: 16,
+            border: "1px solid rgba(82, 196, 26, 0.15)",
+          }}
+        >
+          <span style={{ fontSize: 13, color: "#389e0d" }}>
+            ⏳ 正在服务器渲染预览视频，请稍候...
+          </span>
+        </div>
+      )}
+
       <TitleStylePanel
         settings={titleSettings}
         onUpdatePosition={onUpdatePosition}
diff --git a/apps/web/src/pages/generate/hooks/useServerPreview.ts b/apps/web/src/pages/generate/hooks/useServerPreview.ts
new file mode 100644
index 000000000..ac6f0f90c
--- /dev/null
+++ b/apps/web/src/pages/generate/hooks/useServerPreview.ts
@@ -0,0 +1,294 @@
+/**
+ * 服务器渲染预览 Hook
+ *
+ * 核心职责：
+ * 1. 调用 POST /generation/preview 创建服务器预览渲染任务
+ * 2. 轮询 GET /generation/preview/{task_id} 直到完成
+ * 3. 返回服务器渲染的真实视频 URL（供 <video> 标签播放）
+ * 4. 检测配置变更，标记预览失效（stale）或自动重新渲染
+ * 5. 网络错误自动重试 2 次
+ *
+ * 状态机：
+ *   idle → loading → ready → stale (config changed)
+ *                   ↘ failed → idle (retry)
+ */
+import { useState, useCallback, useRef, useEffect } from "react"
+import { createPreview, getPreviewStatus } from "@/api/generation/preview"
+import type { CreatePreviewRequest } from "@/api/generation/types"
+
+export type ServerPreviewStatus = "idle" | "loading" | "ready" | "stale" | "failed"
+
+interface UseServerPreviewOptions {
+  /** 是否启用预览（Step4+ 且有素材和模板时） */
+  enabled: boolean
+  /** 构建预览请求参数（每次 render 调用，获取最新配置） */
+  buildRequest: () => CreatePreviewRequest
+  /** 预览任务创建成功回调 */
+  onPreviewTaskCreated?: (taskId: string, sourceEditPlanId?: string) => void
+}
+
+interface UseServerPreviewReturn {
+  status: ServerPreviewStatus
+  videoUrl: string | null
+  error: string | null
+  /** 进度 0-100 */
+  progress: number
+  /** 手动触发预览创建（"重新预览"按钮或标题变更后手动刷新） */
+  triggerPreview: () => void
+  /** 当前预览任务 ID */
+  taskId: string | null
+}
+
+const POLL_INTERVAL = 2000
+const POLL_TIMEOUT = 120_000
+const MAX_NETWORK_RETRIES = 2
+
+/**
+ * 对配置参数做指纹，用于检测配置是否变化
+ */
+function buildFingerprint(req: CreatePreviewRequest): string {
+  return JSON.stringify({
+    t: req.template_id,
+    a: [...req.asset_ids].sort(),
+    d: req.duration,
+    r: req.video_ratio,
+    v: req.voice_library_id,
+    b: req.bgm_config,
+    title: req.title_config,
+  })
+}
+
+export function useServerPreview({
+  enabled,
+  buildRequest,
+  onPreviewTaskCreated,
+}: UseServerPreviewOptions): UseServerPreviewReturn {
+  const [status, setStatus] = useState<ServerPreviewStatus>("idle")
+  const [videoUrl, setVideoUrl] = useState<string | null>(null)
+  const [error, setError] = useState<string | null>(null)
+  const [progress, setProgress] = useState(0)
+  const [taskId, setTaskId] = useState<string | null>(null)
+
+  const pollTimerRef = useRef<ReturnType<typeof setTimeout> | null>(null)
+  const timeoutTimerRef = useRef<ReturnType<typeof setTimeout> | null>(null)
+  const requestSeqRef = useRef(0)
+  const renderedFingerprintRef = useRef<string>("")
+  const mountedRef = useRef(true)
+  const networkRetriesRef = useRef(0)
+
+  // 始终持有最新的 buildRequest 和回调
+  const buildRequestRef = useRef(buildRequest)
+  buildRequestRef.current = buildRequest
+  const onCreatedRef = useRef(onPreviewTaskCreated)
+  onCreatedRef.current = onPreviewTaskCreated
+
+  /* ── 清理 ── */
+  const clearTimers = useCallback(() => {
+    if (pollTimerRef.current) {
+      clearTimeout(pollTimerRef.current)
+      pollTimerRef.current = null
+    }
+    if (timeoutTimerRef.current) {
+      clearTimeout(timeoutTimerRef.current)
+      timeoutTimerRef.current = null
+    }
+  }, [])
+
+  useEffect(() => {
+    mountedRef.current = true
+    return () => {
+      mountedRef.current = false
+      clearTimers()
+    }
+  }, [clearTimers])
+
+  /* ── 创建预览 + 轮询 ── */
+  const createAndPoll = useCallback(
+    async (request: CreatePreviewRequest, seq: number) => {
+      setStatus("loading")
+      setProgress(0)
+      setError(null)
+      networkRetriesRef.current = 0
+
+      try {
+        const resp = await createPreview(request)
+        if (seq !== requestSeqRef.current || !mountedRef.current) return
+
+        setTaskId(resp.task_id)
+        onCreatedRef.current?.(resp.task_id, resp.source_edit_plan_id)
+
+        let completed = false
+
+        // 超时保护
+        timeoutTimerRef.current = setTimeout(() => {
+          if (completed || seq !== requestSeqRef.current || !mountedRef.current) return
+          completed = true
+          clearTimers()
+          setStatus("failed")
+          setError("预览渲染超时（120秒），请重试")
+        }, POLL_TIMEOUT)
+
+        const poll = async () => {
+          if (completed || seq !== requestSeqRef.current || !mountedRef.current) return
+
+          try {
+            const st = await getPreviewStatus(resp.task_id)
+            if (completed || seq !== requestSeqRef.current || !mountedRef.current) return
+
+            if (st.status === "completed" && st.video_url) {
+              completed = true
+              clearTimers()
+              renderedFingerprintRef.current = buildFingerprint(request)
+              setVideoUrl(st.video_url)
+              setProgress(100)
+              setStatus("ready")
+              setError(null)
+              return
+            }
+
+            if (st.status === "failed" || st.status === "cancelled") {
+              completed = true
+              clearTimers()
+              setStatus("failed")
+              setError(
+                st.status === "cancelled"
+                  ? "预览任务已取消"
+                  : st.error_message || "预览渲染失败，请重试",
+              )
+              return
+            }
+
+            // pending / generating
+            if (typeof st.progress === "number") setProgress(st.progress)
+            pollTimerRef.current = setTimeout(poll, POLL_INTERVAL)
+          } catch (pollErr) {
+            if (completed || seq !== requestSeqRef.current || !mountedRef.current) return
+            if (networkRetriesRef.current < MAX_NETWORK_RETRIES) {
+              networkRetriesRef.current += 1
+              console.warn(
+                `[ServerPreview] 轮询网络错误，第 ${networkRetriesRef.current} 次重试`,
+                pollErr,
+              )
+              pollTimerRef.current = setTimeout(poll, POLL_INTERVAL * 2)
+            } else {
+              completed = true
+              clearTimers()
+              setStatus("failed")
+              setError("网络错误，无法获取预览状态，请重试")
+            }
+          }
+        }
+
+        poll()
+      } catch (createErr) {
+        if (seq !== requestSeqRef.current || !mountedRef.current) return
+        console.error("[ServerPreview] 创建预览任务失败:", createErr)
+
+        const isNetworkError =
+          !!(createErr as { request?: unknown })?.request ||
+          (createErr as { code?: string })?.code === "ERR_NETWORK"
+
+        if (isNetworkError && networkRetriesRef.current < MAX_NETWORK_RETRIES) {
+          networkRetriesRef.current += 1
+          console.warn(`[ServerPreview] 创建任务网络错误，第 ${networkRetriesRef.current} 次重试`)
+          setTimeout(() => {
+            if (seq === requestSeqRef.current && mountedRef.current) {
+              createAndPoll(request, seq)
+            }
+          }, POLL_INTERVAL * 2)
+          return
+        }
+
+        const errData = (
+          createErr as { response?: { data?: { detail?: string; message?: string } } }
+        )?.response?.data
+        setStatus("failed")
+        setError(errData?.detail || errData?.message || "预览任务创建失败，请重试")
+      }
+    },
+    [clearTimers],
+  )
+
+  /* ── 手动触发预览 ── */
+  const triggerPreview = useCallback(() => {
+    if (!enabled) return
+    const request = buildRequestRef.current()
+    if (!request.template_id || request.asset_ids.length === 0) return
+
+    clearTimers()
+    const seq = ++requestSeqRef.current
+    setVideoUrl(null)
+    setTaskId(null)
+    createAndPoll(request, seq)
+  }, [enabled, clearTimers, createAndPoll])
+
+  /* ── 自动触发 + 配置变更检测 ── */
+  // 每次 render 都检查最新配置 fingerprint，与已渲染的 fingerprint 比较
+  const request = enabled ? buildRequest() : null
+  const currentFingerprint = request
+    ? request.template_id && request.asset_ids.length > 0
+      ? buildFingerprint(request)
+      : ""
+    : ""
+
+  // 首次进入自动触发
+  const didInitRef = useRef(false)
+  useEffect(() => {
+    if (!enabled || !currentFingerprint) {
+      didInitRef.current = false
+      // 禁用时取消进行中的轮询，避免回到前序步骤后仍在后台轮询
+      requestSeqRef.current += 1
+      clearTimers()
+      return
+    }
+    if (!didInitRef.current) {
+      didInitRef.current = true
+      renderedFingerprintRef.current = currentFingerprint
+      triggerPreview()
+    }
+  }, [enabled, currentFingerprint, triggerPreview, clearTimers])
+
+  // 配置变更检测：素材/配音/BGM 等变化 → 自动重渲染；标题样式变化 → 标记 stale
+  const prevFingerprintRef = useRef(currentFingerprint)
+  useEffect(() => {
+    if (!enabled || !currentFingerprint) return
+    const prev = prevFingerprintRef.current
+    prevFingerprintRef.current = currentFingerprint
+
+    if (!prev || prev === currentFingerprint) return
+    if (currentFingerprint === renderedFingerprintRef.current) return
+
+    // 配置已变更
+    // 判断是标题样式变更还是素材/配音/BGM 变更
+    const prevParsed = JSON.parse(prev) as Record<string, unknown>
+    const currParsed = JSON.parse(currentFingerprint) as Record<string, unknown>
+    const nonTitleChanged =
+      prevParsed.t !== currParsed.t ||
+      prevParsed.a !== currParsed.a ||
+      prevParsed.d !== currParsed.d ||
+      prevParsed.r !== currParsed.r ||
+      prevParsed.v !== currParsed.v ||
+      JSON.stringify(prevParsed.b) !== JSON.stringify(currParsed.b)
+
+    if (nonTitleChanged) {
+      // 素材/配音/BGM/模板等变化 → 自动重新渲染
+      renderedFingerprintRef.current = currentFingerprint
+      triggerPreview()
+    } else {
+      // 仅标题文字/样式变化 → 标记 stale，不自动重渲染（避免频繁请求）
+      // 实时预览由 CSS TitleOverlay 提供
+      setStatus((s) => (s === "ready" ? "stale" : s))
+    }
+  }, [enabled, currentFingerprint, triggerPreview])
+
+  return {
+    status,
+    videoUrl,
+    error,
+    progress,
+    triggerPreview,
+    taskId,
+  }
+}
+
+export default useServerPreview
diff --git a/apps/web/src/pages/generate/hooks/useStepNavigation.ts b/apps/web/src/pages/generate/hooks/useStepNavigation.ts
index 89d5b7df8..4c2335467 100644
--- a/apps/web/src/pages/generate/hooks/useStepNavigation.ts
+++ b/apps/web/src/pages/generate/hooks/useStepNavigation.ts
@@ -3,7 +3,7 @@
  * 管理步骤切换与各步骤的前置校验
  * 步骤顺序：模板(1) → 素材(2) → 配音(3) → 标题(4) → 预览(5) → 封面(6) → 确认(7)
  *
- * V24: previewReady 改为前端素材加载状态
+ * 服务器预览架构：Step5 需要服务器渲染预览完成才能前进
  */
 import { message } from "antd"
 import type { TitleSettings } from "../types"
@@ -16,7 +16,7 @@ export interface UseStepNavigationOptions {
   selectedMaterials: string[]
   smartSelectedIds: string[]
   titleSettings: TitleSettings
-  /** 预览是否就绪（前端素材已加载） */
+  /** 服务器预览是否已完成（ready 状态） */
   previewReady: boolean
 }
 
@@ -50,13 +50,12 @@ export const useStepNavigation = (options: UseStepNavigationOptions): UseStepNav
       message.warning("请先进行智能匹配并选择素材")
       return
     }
-    // Step3 配音：配音为可选项，不强制校验，用户可跳过
     if (currentStep === 4 && !titleSettings.title.trim()) {
       message.warning("请选择或输入标题")
       return
     }
     if (currentStep === 5 && !previewReady) {
-      message.warning("请先选择素材以预览效果")
+      message.warning("请等待预览视频渲染完成后再继续")
       return
     }
     if (currentStep < 7) {