diff --git a/static/src/components/chat/ChatArea.vue b/static/src/components/chat/ChatArea.vue
index 3add3b9e..15af7650 100644
--- a/static/src/components/chat/ChatArea.vue
+++ b/static/src/components/chat/ChatArea.vue
@@ -1,12 +1,14 @@
 <template>
-  <div
-    class="messages-area messages-area--stick"
-    :class="{ 'messages-area--render-pending': renderPending }"
-    ref="scrollRef"
-  >
+  <div class="chat-area-shell" ref="shellRef">
+    <div
+      class="messages-area messages-area--stick"
+      :class="{ 'messages-area--render-pending': renderPending }"
+      ref="scrollRef"
+    >
     <div class="messages-flow" ref="contentRef">
       <!-- 窗口化渲染：virtua 只挂载可视区+buffer 的消息块，未挂载项按实测高度缓存占位 -->
       <Virtualizer
+        ref="virtualizerRef"
         v-if="stickScrollElement"
         :data="filteredMessages || []"
         :scroll-ref="stickScrollElement"
@@ -676,6 +678,36 @@
       </Virtualizer>
     </div>
     <div class="messages-bottom-spacer" aria-hidden="true"></div>
+    </div>
+    <!-- 左侧用户输入快捷跳转导航：每个真实用户输入一根横线，hover 波浪 + 预览，点击跳转 -->
+    <nav
+      v-if="quickNavItems.length > 0"
+      class="chat-quick-nav"
+      :style="{ '--qn-count': String(quickNavItems.length) }"
+      aria-label="用户输入快捷跳转"
+      @mousemove="onQuickNavMouseMove"
+      @mouseleave="onQuickNavMouseLeave"
+    >
+      <div
+        v-for="(item, i) in quickNavItems"
+        :key="item.msgIndex"
+        class="qn-line"
+        :class="{ 'is-hot': quickNavActiveIndex === i }"
+        :style="{ width: quickNavLineWidth(i) + 'px' }"
+        :ref="(el) => registerQuickNavLine(i, el)"
+        @click="onQuickNavLineClick(item)"
+      ></div>
+    </nav>
+    <div
+      class="quick-nav-preview"
+      :class="{ 'is-visible': quickNavActiveIndex >= 0 }"
+      :style="quickNavPreviewStyle"
+    >
+      <div class="quick-nav-preview-user">{{ quickNavPreviewUser }}</div>
+      <div class="quick-nav-preview-ai">
+        <MarkdownRenderer :content="quickNavPreviewAi" :is-streaming="false" />
+      </div>
+    </div>
   </div>
 </template>
 
@@ -2128,6 +2160,155 @@ function getGeneratingLetters(message: any) {
   return Array.from(label);
 }
 
+// ===== 左侧用户输入快捷跳转导航 =====
+// 数据口径与深度压缩一致：role === 'user' 且 metadata.message_source === 'user'（引导/通知/压缩等不计入）
+const shellRef = ref<HTMLElement | null>(null);
+const virtualizerRef = ref<any>(null);
+const quickNavActiveIndex = ref(-1);
+const quickNavLineEls = new Map<number, HTMLElement>();
+
+const isRealUserNavMessage = (msg: any): boolean => {
+  if (!msg || msg.role !== 'user') {
+    return false;
+  }
+  return String(msg?.metadata?.message_source || 'user').trim().toLowerCase() === 'user';
+};
+
+function extractUserFirstLine(msg: any): string {
+  const content = msg?.content;
+  let text = '';
+  if (typeof content === 'string') {
+    text = content;
+  } else if (Array.isArray(content)) {
+    text = content
+      .filter((it: any) => it && it.type === 'text' && typeof it.text === 'string')
+      .map((it: any) => it.text)
+      .join('\n');
+  } else if (content != null) {
+    text = String(content);
+  }
+  const lines = text
+    .split('\n')
+    .map((l: string) => l.trim())
+    .filter((l: string) => l && !l.startsWith('[系统通知|'));
+  return lines[0] || '（空输入）';
+}
+
+function extractAssistantLastText(msg: any): string {
+  const actions = Array.isArray(msg?.actions) ? msg.actions : [];
+  for (let i = actions.length - 1; i >= 0; i -= 1) {
+    const action = actions[i];
+    if (action?.type === 'text' && typeof action?.content === 'string' && action.content.trim()) {
+      return action.content.trim();
+    }
+  }
+  const content = msg?.content;
+  return typeof content === 'string' ? content.trim() : '';
+}
+
+const quickNavItems = computed(() => {
+  const msgs = getFilteredMessagesSafe();
+  const userIndexes: number[] = [];
+  for (let i = 0; i < msgs.length; i += 1) {
+    if (isRealUserNavMessage(msgs[i])) {
+      userIndexes.push(i);
+    }
+  }
+  return userIndexes.map((msgIndex, k) => {
+    // 该输入所产生的最后一次输出：下一条真实用户输入之前、最后一条 assistant 消息的最终文本
+    const end = k + 1 < userIndexes.length ? userIndexes[k + 1] : msgs.length;
+    let aiText = '';
+    for (let i = end - 1; i > msgIndex; i -= 1) {
+      const m = msgs[i];
+      if (!m || m.role !== 'assistant') {
+        continue;
+      }
+      const text = extractAssistantLastText(m);
+      if (text) {
+        aiText = text;
+        break;
+      }
+    }
+    return {
+      msgIndex,
+      userText: extractUserFirstLine(msgs[msgIndex]),
+      aiText: aiText || '（暂无回复）'
+    };
+  });
+});
+
+const QUICK_NAV_LINE_WIDTHS = [34, 25, 17, 12];
+const QUICK_NAV_LINE_BASE_WIDTH = 8;
+
+function quickNavLineWidth(index: number): number {
+  const active = quickNavActiveIndex.value;
+  if (active < 0) {
+    return QUICK_NAV_LINE_BASE_WIDTH;
+  }
+  const dist = Math.abs(index - active);
+  return QUICK_NAV_LINE_WIDTHS[dist] ?? QUICK_NAV_LINE_BASE_WIDTH;
+}
+
+function registerQuickNavLine(index: number, el: any) {
+  if (el) {
+    quickNavLineEls.set(index, el as HTMLElement);
+  } else {
+    quickNavLineEls.delete(index);
+  }
+}
+
+function onQuickNavMouseMove(event: MouseEvent) {
+  let best = -1;
+  let bestDist = Infinity;
+  quickNavLineEls.forEach((el, i) => {
+    const rect = el.getBoundingClientRect();
+    const d = Math.abs(event.clientY - (rect.top + rect.height / 2));
+    if (d < bestDist) {
+      bestDist = d;
+      best = i;
+    }
+  });
+  quickNavActiveIndex.value = best;
+}
+
+function onQuickNavMouseLeave() {
+  quickNavActiveIndex.value = -1;
+}
+
+function onQuickNavLineClick(item: any) {
+  virtualizerRef.value?.scrollToIndex?.(item.msgIndex, { align: 'start', smooth: true });
+}
+
+// ===== 悬浮预览卡 =====
+const QUICK_NAV_PREVIEW_HEIGHT = 116;
+const quickNavPreviewUser = ref('');
+const quickNavPreviewAi = ref('');
+const quickNavPreviewStyle = ref<Record<string, string>>({});
+
+watch(quickNavActiveIndex, (idx) => {
+  if (idx < 0) {
+    return;
+  }
+  const item = quickNavItems.value[idx];
+  if (!item) {
+    return;
+  }
+  quickNavPreviewUser.value = item.userText;
+  quickNavPreviewAi.value = item.aiText;
+  const shell = shellRef.value;
+  const lineEl = quickNavLineEls.get(idx);
+  if (!shell || !lineEl) {
+    return;
+  }
+  const shellRect = shell.getBoundingClientRect();
+  const lineRect = lineEl.getBoundingClientRect();
+  const centerY = lineRect.top - shellRect.top + lineRect.height / 2;
+  let top = centerY - QUICK_NAV_PREVIEW_HEIGHT / 2;
+  top = Math.max(8, Math.min(top, shellRect.height - QUICK_NAV_PREVIEW_HEIGHT - 8));
+  const left = lineRect.right - shellRect.left + 14;
+  quickNavPreviewStyle.value = { top: `${top}px`, left: `${left}px` };
+});
+
 defineExpose({
   rootEl,
   getThinkingRef,
diff --git a/static/src/styles/components/chat/_chat-area.scss b/static/src/styles/components/chat/_chat-area.scss
index 90300228..fbd6f9a4 100644
--- a/static/src/styles/components/chat/_chat-area.scss
+++ b/static/src/styles/components/chat/_chat-area.scss
@@ -90,6 +90,168 @@
 }
 
 /* 核心聊天区样式，确保对话内容在主面板中可见 */
+.chat-area-shell {
+  flex: 1;
+  min-height: 0;
+  position: relative;
+  display: flex;
+  flex-direction: column;
+}
+
+.chat-area-shell > .messages-area {
+  flex: 1;
+}
+
+/* 左侧用户输入快捷跳转导航 */
+.chat-quick-nav {
+  position: absolute;
+  left: 18px;
+  top: 50%;
+  transform: translateY(-50%);
+  display: flex;
+  flex-direction: column;
+  justify-content: space-between;
+  padding: 10px 8px;
+  height: min(62vh, calc(var(--qn-count, 1) * 9px + 20px));
+  z-index: 30;
+}
+
+.qn-line {
+  height: 2px;
+  width: 8px;
+  border-radius: 1px;
+  background: var(--text-tertiary);
+  opacity: 0.45;
+  cursor: pointer;
+  transition: width 0.16s ease, opacity 0.16s ease, background-color 0.16s ease;
+  position: relative;
+  flex-shrink: 0;
+}
+
+/* 扩大每根线的上下热区，「周围」也能触发波浪 */
+.qn-line::before {
+  content: "";
+  position: absolute;
+  left: -6px;
+  right: -10px;
+  top: -5px;
+  bottom: -5px;
+}
+
+.qn-line.is-hot {
+  background: var(--text-primary);
+  opacity: 1;
+}
+
+/* 悬浮预览卡：上行用户原始输入，下行该轮最后一次 AI 输出（Markdown 渲染） */
+.quick-nav-preview {
+  position: absolute;
+  width: 340px;
+  height: 116px;
+  display: flex;
+  flex-direction: column;
+  background: var(--surface-raised);
+  border: 1px solid var(--border-default);
+  border-radius: 12px;
+  box-shadow: var(--shadow-mid);
+  padding: 14px 16px;
+  z-index: 40;
+  pointer-events: none;
+  opacity: 0;
+  transform: translateX(-4px);
+  transition: opacity 0.12s ease, transform 0.12s ease;
+  overflow: hidden;
+}
+
+.quick-nav-preview.is-visible {
+  opacity: 1;
+  transform: translateX(0);
+}
+
+.quick-nav-preview-user {
+  flex-shrink: 0;
+  font-weight: 600;
+  font-size: 13.5px;
+  line-height: 1.45;
+  color: var(--text-primary);
+  white-space: nowrap;
+  overflow: hidden;
+  text-overflow: ellipsis;
+  margin-bottom: 8px;
+}
+
+.quick-nav-preview-ai {
+  flex: 1;
+  min-height: 0;
+  overflow: hidden;
+  font-size: 12.5px;
+  line-height: 1.6;
+  color: var(--text-secondary);
+}
+
+.quick-nav-preview-ai :deep(.markdown-renderer) {
+  font-size: inherit;
+  line-height: inherit;
+  color: inherit;
+}
+
+.quick-nav-preview-ai :deep(p) {
+  margin: 0 0 4px;
+}
+
+.quick-nav-preview-ai :deep(ul),
+.quick-nav-preview-ai :deep(ol) {
+  margin: 0 0 4px;
+  padding-left: 18px;
+}
+
+.quick-nav-preview-ai :deep(li) {
+  margin-bottom: 2px;
+}
+
+.quick-nav-preview-ai :deep(li:last-child),
+.quick-nav-preview-ai :deep(p:last-child) {
+  margin-bottom: 0;
+}
+
+.quick-nav-preview-ai :deep(strong) {
+  color: var(--text-primary);
+  font-weight: 600;
+}
+
+.quick-nav-preview-ai :deep(code) {
+  font-size: 12px;
+  font-family: ui-monospace, "SF Mono", Menlo, monospace;
+  background: var(--surface-muted);
+  border-radius: 4px;
+  padding: 0 4px;
+}
+
+.quick-nav-preview-ai :deep(pre) {
+  margin: 0 0 4px;
+  white-space: pre-wrap;
+  word-break: break-all;
+  font-size: 12px;
+}
+
+.quick-nav-preview-ai :deep(h1),
+.quick-nav-preview-ai :deep(h2),
+.quick-nav-preview-ai :deep(h3),
+.quick-nav-preview-ai :deep(h4),
+.quick-nav-preview-ai :deep(h5),
+.quick-nav-preview-ai :deep(h6) {
+  font-size: 12.5px;
+  font-weight: 600;
+  color: var(--text-primary);
+  margin: 0 0 4px;
+}
+
+@media (max-width: 640px) {
+  .chat-quick-nav {
+    display: none;
+  }
+}
+
 .messages-area {
   flex: 1;
   overflow-y: auto;