diff --git a/frontend/src/core/features/block_editor/BlockEditorEntry.vue b/frontend/src/core/features/block_editor/BlockEditorEntry.vue
index 4a0ee313a..d237b6716 100644
--- a/frontend/src/core/features/block_editor/BlockEditorEntry.vue
+++ b/frontend/src/core/features/block_editor/BlockEditorEntry.vue
@@ -388,6 +388,7 @@ const _handleAIAction = async (e: Event) => {
         insertTo: range.to,
         modifiedText: range.modifiedText,
         originalContent: range.originalContent,
+        modifiedContent: range.modifiedContent,
       })
     },
   }, true) // reviewMode is now always true
diff --git a/frontend/src/core/features/block_editor/composables/useAICommand.ts b/frontend/src/core/features/block_editor/composables/useAICommand.ts
index 27e91d0f4..e63120129 100644
--- a/frontend/src/core/features/block_editor/composables/useAICommand.ts
+++ b/frontend/src/core/features/block_editor/composables/useAICommand.ts
@@ -24,7 +24,7 @@ export interface AIStreamCallbacks {
   /** 流式完成 */
   onDone: (fullContent: string) => void
   /** 审阅模式：AI 输出完成并插入后的位置范围和对比文本 */
-  onReviewReady?: (range: { from: number; to: number; originalText: string; modifiedText: string; originalContent?: any[] }) => void
+  onReviewReady?: (range: { from: number; to: number; originalText: string; modifiedText: string; originalContent?: any[]; modifiedContent?: any[] }) => void
   /** 出错 */
   onError: (error: string) => void
 }
@@ -484,6 +484,10 @@ async function callInlineAI(options: InlineAICallOptions) {
     if (options.reviewMode && originalInsertAt !== null) {
       const reviewTo = editor.state.selection.to
       const modifiedText = editor.state.doc.textBetween(originalInsertAt, reviewTo, '\n', '\n')
+      // 捕获修改后内容的 PM 结构化节点，用于块级 diff
+      const modifiedContent = editor.state.doc
+        .slice(originalInsertAt, reviewTo)
+        .toJSON()?.content
       options.callbacks?.onReviewReady?.(
         {
           from: originalInsertAt,
@@ -491,6 +495,7 @@ async function callInlineAI(options: InlineAICallOptions) {
           originalText: options.context.selectedText,
           modifiedText,
           originalContent: (options as any)._originalContent,
+          modifiedContent,
         },
       )
     } else {
diff --git a/frontend/src/core/features/block_editor/composables/useAIReview.ts b/frontend/src/core/features/block_editor/composables/useAIReview.ts
index 8d520706d..dd6941006 100644
--- a/frontend/src/core/features/block_editor/composables/useAIReview.ts
+++ b/frontend/src/core/features/block_editor/composables/useAIReview.ts
@@ -17,6 +17,7 @@ import { ref, type Ref } from 'vue'
 import type { Editor } from '@tiptap/core'
 import { Decoration, DecorationSet } from '@tiptap/pm/view'
 import { computeDiff } from '../plugins/ai-review/diff'
+import { computeStructuredDiff } from '../plugins/ai-review/structuredDiff'
 import { buildDecorationSet, createDeleteWidgetDom } from '../plugins/ai-review/decorations'
 import {
   reviewState,
@@ -36,6 +37,8 @@ export interface ReviewStartOptions {
   modifiedText: string
   /** 原始文档结构（ProseMirror JSON，用于 rejectAll 恢复段落结构） */
   originalContent?: any[]
+  /** 修改后文档结构（ProseMirror JSON，用于块级 diff） */
+  modifiedContent?: any[]
 }
 
 export function useAIReview(editorRef: Ref<Editor | null>) {
@@ -96,8 +99,10 @@ export function useAIReview(editorRef: Ref<Editor | null>) {
 
     const { originalText, insertFrom, modifiedText, insertTo } = opts
 
-    // 1. 计算 diff
-    const diffSegments = computeDiff(originalText, modifiedText)
+    // 1. 计算 diff（优先使用块级结构化 diff）
+    const diffSegments = (opts.originalContent && opts.modifiedContent)
+      ? computeStructuredDiff(opts.originalContent, opts.modifiedContent)
+      : computeDiff(originalText, modifiedText)
     const nonEqualSegs = diffSegments.filter(s => s.type !== 'equal')
 
     // 2. 构建 segment 信息列表 + DecorationSet（含位置）
diff --git a/frontend/src/core/features/block_editor/plugins/ai-review/structuredDiff.ts b/frontend/src/core/features/block_editor/plugins/ai-review/structuredDiff.ts
new file mode 100644
index 000000000..f6b7c1e66
--- /dev/null
+++ b/frontend/src/core/features/block_editor/plugins/ai-review/structuredDiff.ts
@@ -0,0 +1,97 @@
+/**
+ * plugins/ai-review/structuredDiff.ts — 块级结构化差异算法
+ *
+ * 将 ProseMirror JSON 节点数组按块对齐，跳过未变更的整块段落，
+ * 仅在变更块内部执行字符级 LCS diff。
+ *
+ * 相比纯字符级 diff 的优势：
+ * - 未变更的整块段落不产生任何 decoration（用户不会看到"无关文本被灰色覆盖"）
+ * - diff 不会跨块边界，避免块间误匹配
+ * - 与 ProseMirror 文档模型天然对齐
+ *
+ * 用法：当 originalContent（原始 PM 节点数组）和 modifiedContent（修改后 PM 节点数组）
+ * 同时存在时，此函数替代 computeDiff。
+ */
+
+import { computeDiff, type DiffSegment } from './diff'
+
+/** ProseMirror JSON 节点（简化接口） */
+interface PMNode {
+  type: string
+  content?: PMNode[]
+  text?: string
+  [key: string]: unknown
+}
+
+/**
+ * 提取 PM 节点的纯文本内容（递归遍历 content 数组）。
+ * 与 ProseMirror 的 textBetween('', '') 行为一致。
+ */
+function extractNodeText(node: PMNode): string {
+  if (node.type === 'text') return node.text || ''
+  if (!node.content || node.content.length === 0) return ''
+  return node.content.map(extractNodeText).join('')
+}
+
+/**
+ * 块级结构化 diff。
+ *
+ * @param originalContent  原始内容的 PM JSON 节点数组（doc.slice().toJSON().content）
+ * @param modifiedContent  修改后内容的 PM JSON 节点数组
+ * @returns DiffSegment[] 可直接输入 buildDecorationSet
+ *
+ * 算法：
+ * 1. 按索引对齐原始与修改的块
+ * 2. 文本完全相同的块 → 单个 equal 段（跳过 decoration）
+ * 3. 文本不同的块 → 在块范围内执行字符级 LCS diff
+ * 4. 仅出现在原始中的块 → delete 段
+ * 5. 仅出现在修改中的块 → insert 段
+ * 6. 块间 \n 作为独立 equal 段插入，维持 charOffset 与 textBetween 一致
+ */
+export function computeStructuredDiff(
+  originalContent: PMNode[],
+  modifiedContent: PMNode[],
+): DiffSegment[] {
+  if (!originalContent || originalContent.length === 0) {
+    return [{ type: 'insert', original: '', modified: modifiedContent.map(extractNodeText).join('\n') }]
+  }
+  if (!modifiedContent || modifiedContent.length === 0) {
+    return [{ type: 'delete', original: originalContent.map(extractNodeText).join('\n'), modified: '' }]
+  }
+
+  const origTexts = originalContent.map(extractNodeText)
+  const modTexts = modifiedContent.map(extractNodeText)
+  const maxLen = Math.max(origTexts.length, modTexts.length)
+
+  const segments: DiffSegment[] = []
+
+  for (let i = 0; i < maxLen; i++) {
+    // 块间分隔符：\n 作为独立 equal 段
+    if (i > 0) {
+      segments.push({ type: 'equal', original: '\n', modified: '\n' })
+    }
+
+    const orig = i < origTexts.length ? origTexts[i] : ''
+    const mod = i < modTexts.length ? modTexts[i] : ''
+
+    if (orig === mod) {
+      // ── 未变更块：单段 equal，不产生 decoration ──
+      if (orig !== '') {
+        segments.push({ type: 'equal', original: orig, modified: mod })
+      }
+      // 空块跳过（不输出，保留位置计数但装饰系统会忽略）
+    } else if (orig === '') {
+      // ── 新增块 ──
+      segments.push({ type: 'insert', original: '', modified: mod })
+    } else if (mod === '') {
+      // ── 删除块 ──
+      segments.push({ type: 'delete', original: orig, modified: '' })
+    } else {
+      // ── 变更块：块内字符级 LCS diff ──
+      const innerSegs = computeDiff(orig, mod)
+      segments.push(...innerSegs)
+    }
+  }
+
+  return segments
+}