diff --git a/src/renderer/src/i18n/zh.ts b/src/renderer/src/i18n/zh.ts
index df9ddbca..46cf87c4 100644
--- a/src/renderer/src/i18n/zh.ts
+++ b/src/renderer/src/i18n/zh.ts
@@ -698,6 +698,7 @@ export const zh: Record<string, string> = {
   "Working…": "处理中…",
   "Waiting for the {name} sign-in in your browser (check {check} of {checks}).": "正在等待你在浏览器中完成 {name} 登录（第 {check}/{checks} 次检查）。",
   "Stop waiting": "停止等待",
+  "People to mention": "可提及的人",
   "Layout": "布局",
   "View": "视图",
   "Run status": "运行状态",
diff --git a/src/renderer/src/pages/chat/MentionTextarea.tsx b/src/renderer/src/pages/chat/MentionTextarea.tsx
index ecadb095..ebb7587c 100644
--- a/src/renderer/src/pages/chat/MentionTextarea.tsx
+++ b/src/renderer/src/pages/chat/MentionTextarea.tsx
@@ -1,4 +1,5 @@
-import { useRef, useState, type MutableRefObject } from "react";
+import { t } from "../../i18n/i18n";
+import { useId, useRef, useState, type MutableRefObject } from "react";
 import { Avatar } from "../../shared/ui";
 import type { AgentRecord, EmployeeRecord } from "../../../../shared/domain";
 import { canonicalMentionHandle } from "../../../../shared/mention-handles";
@@ -40,6 +41,7 @@ export function MentionTextarea({
 }) {
   const [query, setQuery] = useState<string | null>(null);
   const [index, setIndex] = useState(0);
+  const listId = useId();
   const anchor = useRef(0);
   const innerRef = useRef<HTMLTextAreaElement | null>(null);
   const ref = textareaRef ?? innerRef;
@@ -52,6 +54,7 @@ export function MentionTextarea({
     : [];
 
   const close = () => setQuery(null);
+  const open = !disabled && query !== null && filtered.length > 0;
 
   const insertMention = (handle: string) => {
     const node = ref.current;
@@ -81,6 +84,8 @@ export function MentionTextarea({
   };
 
   const handleKeyDown = (event: React.KeyboardEvent<HTMLTextAreaElement>) => {
+    // While an input method is composing, Enter and Tab confirm its text; they never pick a person or send.
+    if (event.nativeEvent.isComposing || event.keyCode === 229) return;
     if (query !== null && filtered.length > 0) {
       if (event.key === "ArrowDown") {
         event.preventDefault();
@@ -111,8 +116,8 @@ export function MentionTextarea({
 
   return (
     <div style={{ position: "relative" }}>
-      {!disabled && query !== null && filtered.length > 0 && (
-        <div style={{
+      {open && (
+        <div id={listId} role="listbox" aria-label={t("People to mention")} style={{
           position: "absolute",
           bottom: "100%",
           left: 0,
@@ -129,7 +134,11 @@ export function MentionTextarea({
           {filtered.map((c, i) => (
             <button
               key={c.handle}
+              id={`${listId}-${i}`}
               type="button"
+              role="option"
+              aria-selected={i === index}
+              tabIndex={-1}
               onMouseDown={(e) => { e.preventDefault(); insertMention(c.handle); }}
               style={{
                 display: "flex",
@@ -158,6 +167,9 @@ export function MentionTextarea({
         rows={rows}
         disabled={disabled}
         aria-label={ariaLabel}
+        aria-autocomplete="list"
+        aria-controls={open ? listId : undefined}
+        aria-activedescendant={open ? `${listId}-${index}` : undefined}
         style={{
           width: "100%",
           border: 0,
diff --git a/tests/e2e/keyboard.spec.ts b/tests/e2e/keyboard.spec.ts
index c0f33088..476cebe1 100644
--- a/tests/e2e/keyboard.spec.ts
+++ b/tests/e2e/keyboard.spec.ts
@@ -70,3 +70,37 @@ test("a dialog keeps the keyboard inside it, closes on Escape, and gives focus b
     await closeApp(app);
   }
 });
+
+test("mention suggestions are announced, and an input method's Enter never picks a person", async () => {
+  const profileDir = join(tmpdir(), `agentcompany-new-e2e-mention-${randomUUID()}`);
+  mkdirSync(profileDir, { recursive: true });
+  const builtinDir = seedBuiltinSkillsFixture(join(tmpdir(), `agentcompany-new-e2e-mention-builtin-${randomUUID()}`));
+  const app = await electron.launch({
+    args: [resolve("out/main/index.js")],
+    env: { ...process.env, AGENTCOMPANY_NEW_PROFILE_DIR: profileDir, AGENTCOMPANY_NEW_AUTORUN: "0", AGENTCOMPANY_NEW_BUILTIN_SKILLS_DIR: builtinDir },
+  });
+  try {
+    const page = await app.firstWindow();
+    await onboard(page, "Mention Co");
+    await page.getByRole("button", { name: "Messages" }).click();
+    const composer = page.getByRole("textbox", { name: "Message" });
+    await composer.fill("@");
+    await composer.press("End");
+    await composer.type("c");
+    const list = page.getByRole("listbox", { name: "People to mention" });
+    await expect(list).toBeVisible();
+    const active = await composer.getAttribute("aria-activedescendant");
+    expect(active).toBeTruthy();
+    await expect(list.locator(`[id="${active}"]`)).toHaveAttribute("aria-selected", "true");
+    // An Enter that confirms composed text (isComposing) leaves the words as typed.
+    await composer.evaluate((node) => node.dispatchEvent(new KeyboardEvent("keydown", { key: "Enter", isComposing: true, bubbles: true, cancelable: true })));
+    await expect(composer).toHaveValue("@c");
+    await expect(list).toBeVisible();
+    // A plain Enter picks the highlighted person.
+    await composer.press("Enter");
+    await expect(composer).toHaveValue(/^@\S+ $/);
+    await expect(list).toHaveCount(0);
+  } finally {
+    await closeApp(app);
+  }
+});