diff --git a/apps/web/src/pages/generate/components/Step4TitleSettings.tsx b/apps/web/src/pages/generate/components/Step4TitleSettings.tsx
index 064bc167a..6f8500519 100644
--- a/apps/web/src/pages/generate/components/Step4TitleSettings.tsx
+++ b/apps/web/src/pages/generate/components/Step4TitleSettings.tsx
@@ -9,12 +9,13 @@
  * - 标题样式（字体/颜色/位置/大小/粗斜描边/预设）：全局统一
  */
 import React, { useMemo, useState } from "react"
-import { AutoComplete, Input, message } from "antd"
+import { Input, message } from "antd"
 import { LoadingOutlined } from "@ant-design/icons"
 import type { TitleSettings } from "../types"
 import { POSITION_OPTIONS, FONT_OPTIONS } from "../constants"
 import { useStep4Title } from "../hooks/useStep4Title"
 import AiTitleGenerator from "./title/AiTitleGenerator"
+import TitleLibraryAutoComplete from "./title/TitleLibraryAutoComplete"
 import TitleStylePanel from "./title/TitleStylePanel"
 import { AI_TITLE_TEMPLATES } from "../constants"
 
@@ -201,21 +202,14 @@ const Step4TitleSettings: React.FC<Step4TitleSettingsProps> = (props) => {
               </div>
               <div className="xx-form-field">
                 <label>标题</label>
-                <AutoComplete
-                  placeholder="输入标题文字…"
-                  allowClear
-                  maxLength={50}
-                  style={{ width: "100%" }}
-                  value={(previewTitles?.[0] ?? t.titleSettings.title) || undefined}
+                <TitleLibraryAutoComplete
+                  placeholder="输入或从标题库选择"
+                  value={previewTitles?.[0] ?? t.titleSettings.title}
                   onChange={(val) => {
                     t.updateTitle(val || "")
                     onPreviewTitlesChange?.([val || ""])
                   }}
                   options={titleOptions}
-                  filterOption={(inputValue, option) => {
-                    const title = (option?.label || option?.value || "") as string
-                    return title.toLowerCase().includes((inputValue || "").toLowerCase())
-                  }}
                 />
               </div>
             </>
@@ -269,17 +263,11 @@ const Step4TitleSettings: React.FC<Step4TitleSettingsProps> = (props) => {
           {Array.from({ length: previewCount }, (_, i) => (
             <div className="xx-form-field" key={i}>
               <label>视频 {i + 1} 标题</label>
-              <AutoComplete
-                placeholder={`视频 ${i + 1} 的标题…`}
-                maxLength={50}
-                style={{ width: "100%" }}
-                value={previewTitles?.[i] || undefined}
-                onChange={(val) => updateVariantTitle(i, val || "")}
+              <TitleLibraryAutoComplete
+                placeholder={`输入或选择视频 ${i + 1} 的标题`}
+                value={previewTitles?.[i] || ""}
+                onChange={(val) => updateVariantTitle(i, val)}
                 options={titleOptions}
-                filterOption={(inputValue, option) => {
-                  const title = (option?.label || option?.value || "") as string
-                  return title.toLowerCase().includes((inputValue || "").toLowerCase())
-                }}
               />
             </div>
           ))}
diff --git a/apps/web/src/pages/generate/components/title/TitleLibraryAutoComplete.tsx b/apps/web/src/pages/generate/components/title/TitleLibraryAutoComplete.tsx
new file mode 100644
index 000000000..72cdd8ed6
--- /dev/null
+++ b/apps/web/src/pages/generate/components/title/TitleLibraryAutoComplete.tsx
@@ -0,0 +1,75 @@
+/**
+ * 标题库 AutoComplete（Issue #1737）
+ *
+ * 原生 antd AutoComplete（combobox 模式）的两个行为不符合产品预期：
+ * 1. combobox 默认 showAction=[]，输入框聚焦时下拉不展开——用户必须先打字才能看到标题库，
+ *    且组件无下拉箭头，视觉上是"纯输入框"，不知道标题库里已有标题可选。
+ * 2. 空态聚焦不展示任何标题库内容。
+ *
+ * 本组件封装修复：
+ * - 受控 open：聚焦（且标题库非空）即展开，展示全部标题；失焦/选中/Esc 关闭
+ *   （rc-select 失焦会主动 onToggleOpen(false)，onOpenChange 同步状态即可，不会死循环）
+ * - suffixIcon 加下拉三角，视觉提示"可选择"；有值时 allowClear 的清除按钮照常出现
+ * - 输入文字时由 filterOption 过滤（空串展示全部）
+ * - 保留 combobox 自由输入能力：用户可输入标题库之外的自定义标题
+ */
+import React, { useState } from "react"
+import { AutoComplete } from "antd"
+import { DownOutlined } from "@ant-design/icons"
+import type { AutoCompleteProps } from "antd"
+
+export interface TitleOption {
+  label: string
+  value: string
+}
+
+interface TitleLibraryAutoCompleteProps {
+  value: string
+  onChange: (val: string) => void
+  options: TitleOption[]
+  placeholder?: string
+  allowClear?: boolean
+  maxLength?: number
+  style?: React.CSSProperties
+}
+
+const TitleLibraryAutoComplete: React.FC<TitleLibraryAutoCompleteProps> = ({
+  value,
+  onChange,
+  options,
+  placeholder = "输入或从标题库选择",
+  allowClear = true,
+  maxLength = 50,
+  style,
+}) => {
+  const [open, setOpen] = useState(false)
+  const hasTitles = options.length > 0
+
+  const filterOption: AutoCompleteProps["filterOption"] = (inputValue, option) => {
+    const title = (option?.label || option?.value || "") as string
+    return title.toLowerCase().includes((inputValue || "").toLowerCase())
+  }
+
+  return (
+    <AutoComplete
+      value={value || undefined}
+      onChange={(val) => onChange(val || "")}
+      options={options}
+      filterOption={filterOption}
+      open={open}
+      onOpenChange={setOpen}
+      onFocus={() => {
+        // 标题库为空时不展开（避免弹出"暂无数据"空壳）
+        if (hasTitles) setOpen(true)
+      }}
+      onSelect={() => setOpen(false)}
+      suffixIcon={<DownOutlined style={{ color: "var(--text-secondary, #bbb)", fontSize: 12 }} />}
+      placeholder={placeholder}
+      allowClear={allowClear}
+      maxLength={maxLength}
+      style={{ width: "100%", ...style }}
+    />
+  )
+}
+
+export default TitleLibraryAutoComplete
diff --git a/apps/web/src/test/pages/generate/title-library-autocomplete.test.tsx b/apps/web/src/test/pages/generate/title-library-autocomplete.test.tsx
new file mode 100644
index 000000000..b8a05188d
--- /dev/null
+++ b/apps/web/src/test/pages/generate/title-library-autocomplete.test.tsx
@@ -0,0 +1,126 @@
+/**
+ * TitleLibraryAutoComplete 单测（Issue #1737）
+ *
+ * 覆盖：
+ * - 聚焦空输入框 → 下拉立即展开，展示标题库全部标题（原生 AutoComplete 聚焦不展开，此为本工单核心修复）
+ * - 输入关键词 → 下拉只显示匹配项
+ * - 点击下拉项 → onChange 回填所选标题
+ * - 自由输入自定义标题 → onChange 正常透传，不被下拉干扰
+ * - 标题库为空 → 聚焦不展开（不出"暂无数据"空壳）
+ * - 选中后下拉关闭
+ */
+import { describe, it, expect, vi } from "vitest"
+import { render, screen, waitFor, fireEvent } from "@testing-library/react"
+import userEvent from "@testing-library/user-event"
+import TitleLibraryAutoComplete from "@/pages/generate/components/title/TitleLibraryAutoComplete"
+
+const OPTIONS = [
+  { label: "永康这家面馆绝了", value: "永康这家面馆绝了" },
+  { label: "永康美食探店vlog", value: "永康美食探店vlog" },
+  { label: "萌宠日常第一天", value: "萌宠日常第一天" },
+]
+
+function renderBox(initialValue = "", opts = OPTIONS) {
+  const onChange = vi.fn()
+  const result = render(
+    <TitleLibraryAutoComplete
+      value={initialValue}
+      onChange={onChange}
+      options={opts}
+      placeholder="输入或从标题库选择"
+    />,
+  )
+  return { onChange, ...result }
+}
+
+/** 聚焦输入框（combobox role） */
+function focusInput() {
+  const input = screen.getByRole("combobox") as HTMLInputElement
+  fireEvent.focus(input)
+  return input
+}
+
+/** 取下拉中实际可见的选项（rc-virtual-list 渲染为 .ant-select-item-option；role=option 的 listbox 是 a11y 哨兵） */
+function getVisibleOptions(): HTMLElement[] {
+  const dropdown = document.querySelector(".ant-select-dropdown:not(.ant-select-dropdown-hidden)")
+  if (!dropdown) return []
+  return Array.from(dropdown.querySelectorAll(".ant-select-item-option")) as HTMLElement[]
+}
+
+describe("TitleLibraryAutoComplete (#1737)", () => {
+  it("聚焦空输入框时下拉展开并展示标题库全部标题", async () => {
+    renderBox()
+    expect(screen.queryByRole("listbox")).not.toBeInTheDocument()
+
+    focusInput()
+
+    await screen.findByRole("listbox")
+    await waitFor(() => expect(getVisibleOptions()).toHaveLength(3))
+    const options = getVisibleOptions()
+    expect(options[0]).toHaveTextContent("永康这家面馆绝了")
+    expect(options[2]).toHaveTextContent("萌宠日常第一天")
+  })
+
+  it("输入关键词时下拉只显示匹配项", async () => {
+    const user = userEvent.setup()
+    renderBox()
+    const input = screen.getByRole("combobox")
+    await user.click(input)
+    await screen.findByRole("listbox")
+
+    await user.type(input, "永康")
+    await waitFor(() => expect(getVisibleOptions()).toHaveLength(2))
+    const options = getVisibleOptions()
+    expect(options.every((o) => o.textContent?.includes("永康"))).toBe(true)
+  })
+
+  it("点击下拉项后 onChange 回填标题且下拉关闭", async () => {
+    const user = userEvent.setup()
+    const { onChange } = renderBox()
+    const input = screen.getByRole("combobox") as HTMLInputElement
+    await user.click(input)
+    await screen.findByRole("listbox")
+
+    await user.click(screen.getByText("萌宠日常第一天"))
+
+    await waitFor(() => {
+      expect(onChange).toHaveBeenCalledWith("萌宠日常第一天")
+    })
+    await waitFor(() => {
+      expect(screen.queryByRole("listbox")).not.toBeInTheDocument()
+    })
+  })
+
+  it("自由输入自定义标题时 onChange 正常透传（不被下拉干扰）", async () => {
+    const user = userEvent.setup()
+    const { onChange } = renderBox()
+    const input = screen.getByRole("combobox")
+    await user.click(input)
+
+    await user.type(input, "我自己编的标题XYZ")
+    await waitFor(() => {
+      expect(onChange).toHaveBeenCalledWith("我自己编的标题XYZ")
+    })
+    // 输入无匹配关键词，下拉无 option 时不阻塞输入
+    expect(input).toHaveValue("我自己编的标题XYZ")
+  })
+
+  it("标题库为空时聚焦不展开下拉", async () => {
+    renderBox("", [])
+    focusInput()
+    // 等一帧确认没有 listbox
+    await new Promise((r) => setTimeout(r, 50))
+    expect(screen.queryByRole("listbox")).not.toBeInTheDocument()
+  })
+
+  it("渲染下拉箭头图标作为可选择提示", () => {
+    const { container } = renderBox()
+    // antd 后缀图标在 .ant-select-arrow 内
+    expect(container.querySelector(".ant-select-arrow")).toBeInTheDocument()
+  })
+
+  it("有初始值时输入框正常展示", () => {
+    renderBox("已有标题")
+    expect(screen.getByRole("combobox")).toHaveValue("已有标题")
+  })
+})