diff --git a/web/src/app/AppShell.tsx b/web/src/app/AppShell.tsx
index 5ffc15f0..879d616a 100644
--- a/web/src/app/AppShell.tsx
+++ b/web/src/app/AppShell.tsx
@@ -48,10 +48,15 @@ export function AppShell() {
   // and NewFriendsView's list (['friend-requests','all']) both refetch on invalidation. Listening
   // here rather than in those views keeps the badge live no matter which page the user is on.
   useEffect(() => {
-    return subscribeTopicInfo((_topicName, info) => {
+    return subscribeTopicInfo((topicName, info) => {
       if (info?.event?.startsWith('friend.request.')) {
         queryClient.invalidateQueries({ queryKey: ['friend-requests'] });
       }
+      if (info?.event === 'group.member.profile.updated' && topicName.startsWith('grp')) {
+        queryClient.invalidateQueries({ queryKey: ['group-members', topicName] });
+        queryClient.invalidateQueries({ queryKey: ['group-members-preview', topicName] });
+        queryClient.invalidateQueries({ queryKey: ['group-my-profile', topicName] });
+      }
     });
   }, [queryClient]);
   // "sys" has its own authoritative unread source in entry_badges (bootstrap.ts) -- excluded here
diff --git a/web/src/features/groups/GroupAdminModal.tsx b/web/src/features/groups/GroupAdminModal.tsx
index 077160d6..34ba24ee 100644
--- a/web/src/features/groups/GroupAdminModal.tsx
+++ b/web/src/features/groups/GroupAdminModal.tsx
@@ -24,6 +24,7 @@ import {
 } from '@/lib/api/groups';
 import { avatarBgClass, avatarLetter } from '@/lib/avatar';
 import { useEscapeKey } from '@/lib/hooks';
+import { groupMemberDisplayName } from '@/lib/messages/group-member-name';
 import { requestConfirm } from '@/stores/confirmDialog';
 import { requestActionToken } from '@/stores/securityChallenge';
 import { useSessionStore } from '@/stores/session';
@@ -288,9 +289,9 @@ function MemberPickerList({
           className="flex w-full items-center gap-3 rounded-lg px-3 py-2 text-left hover:bg-surface-rail disabled:opacity-50"
         >
           <span className={`grid h-9 w-9 flex-none place-items-center rounded-lg text-sm font-medium text-white ${avatarBgClass(m.user_id)}`}>
-            {avatarLetter(m.display_name)}
+            {avatarLetter(groupMemberDisplayName(m))}
           </span>
-          <span className="truncate text-sm text-text-body">{m.display_name || m.user_id}</span>
+          <span className="truncate text-sm text-text-body">{groupMemberDisplayName(m)}</span>
         </button>
       ))}
     </>
@@ -370,9 +371,9 @@ function AdminsSubView({
           {admins.map((a) => (
             <div key={a.user_id} className="flex items-center gap-3 px-3 py-2">
               <span className={`grid h-9 w-9 flex-none place-items-center rounded-lg text-sm font-medium text-white ${avatarBgClass(a.user_id)}`}>
-                {avatarLetter(a.display_name)}
+                {avatarLetter(groupMemberDisplayName(a))}
               </span>
-              <span className="flex-1 truncate text-sm text-text-body">{a.display_name || a.user_id}</span>
+              <span className="flex-1 truncate text-sm text-text-body">{groupMemberDisplayName(a)}</span>
               <button
                 type="button"
                 onClick={() => removeMutation.mutate(a.user_id)}
@@ -445,7 +446,8 @@ function MutesSubView({ topicId, muted, onClose }: { topicId: string; muted: Gro
       ) : (
         <>
           {muted.map((m) => {
-            const name = memberByUserId.get(m.user_id)?.display_name || m.user_id;
+            const member = memberByUserId.get(m.user_id);
+            const name = member ? groupMemberDisplayName(member) : m.user_id;
             return (
               <div key={m.user_id} className="flex items-center gap-3 px-3 py-2">
                 <span className={`grid h-9 w-9 flex-none place-items-center rounded-lg text-sm font-medium text-white ${avatarBgClass(m.user_id)}`}>
@@ -500,7 +502,7 @@ function TransferOwnerSubView({ topicId, groupVersion, onClose }: { topicId: str
         cacheKey="eligible-owner"
         opts={{ eligibleRole: 'owner' }}
         onPick={async (m) => {
-          if (!(await requestConfirm({ message: `确定将群主转让给 ${m.display_name || m.user_id} 吗？此操作不可撤销。`, danger: true }))) return;
+          if (!(await requestConfirm({ message: `确定将群主转让给 ${groupMemberDisplayName(m)} 吗？此操作不可撤销。`, danger: true }))) return;
           const actionToken = await requestActionToken({ scene: 'group_owner_transfer', actionDescription: '转让群主' });
           if (!actionToken) return;
           transferMutation.mutate({ userId: m.user_id, actionToken });
diff --git a/web/src/features/groups/GroupDetailColumn.tsx b/web/src/features/groups/GroupDetailColumn.tsx
index 2dd72349..30e1f35f 100644
--- a/web/src/features/groups/GroupDetailColumn.tsx
+++ b/web/src/features/groups/GroupDetailColumn.tsx
@@ -31,6 +31,7 @@ import {
 import type { MediaType } from '@/lib/api/messages';
 import { uploadFile } from '@/lib/api/upload';
 import { MAX_TITLE_LENGTH } from '@/lib/config';
+import { groupMemberDisplayName } from '@/lib/messages/group-member-name';
 import { useTinode } from '@/lib/tinode/hooks';
 import { forgetTopic } from '@/lib/tinode/topics';
 import { requestConfirm } from '@/stores/confirmDialog';
@@ -119,8 +120,7 @@ export function GroupDetailColumn({ topicId, peerName, onClose, onOpenHistory }:
   // GroupAdminModal's join-request badge, so this is a cache hit more often than not).
   const summaryQuery = useQuery({ queryKey: ['group-summary', topicId], queryFn: () => getGroupSummary(topicId) });
   const membersQuery = useQuery({ queryKey: ['group-members-preview', topicId], queryFn: () => getGroupMembers(topicId, {}) });
-  // `GET .../members` never returns `group_nickname` on any item (confirmed live by the old app) --
-  // only this per-user profile endpoint does, so the nickname row needs its own fetch. Uses the
+  // The nickname row needs the per-user profile endpoint. Uses the
   // dedicated `members/me/profile` route, not getGroupMemberProfile(topic, myUserId) -- see that
   // function's own warning for why the generic by-id path 400s on self-lookups.
   const myProfileQuery = useQuery({
@@ -168,6 +168,8 @@ export function GroupDetailColumn({ topicId, peerName, onClose, onOpenHistory }:
     mutationFn: (nickname: string) => updateMyGroupNickname(topicId, nickname, myProfileQuery.data?.version ?? 1),
     onSuccess: () => {
       queryClient.invalidateQueries({ queryKey: ['group-my-profile', topicId, myUserId] });
+      queryClient.invalidateQueries({ queryKey: ['group-members-preview', topicId] });
+      queryClient.invalidateQueries({ queryKey: ['group-members', topicId] });
       setNicknameEditing(false);
     },
     onError: (err) => showError(err, '昵称保存失败'),
@@ -430,12 +432,12 @@ export function GroupDetailColumn({ topicId, peerName, onClose, onOpenHistory }:
                       desktop's 40px (unconditional here before this fix). */}
                   <Avatar
                     id={m.user_id}
-                    name={m.display_name}
+                    name={groupMemberDisplayName(m)}
                     avatarFileId={m.avatar_file_id}
                     className="h-11 w-11 rounded-lg text-sm md:h-10 md:w-10"
                   />
                   <RoleCorner role={m.role} />
-                  <span className="w-full truncate text-center text-[11px] text-text-secondary">{m.display_name || m.user_id}</span>
+                  <span className="w-full truncate text-center text-[11px] text-text-secondary">{groupMemberDisplayName(m)}</span>
                 </button>
               ))}
               {canInvite ? (
diff --git a/web/src/features/groups/GroupMembersModal.tsx b/web/src/features/groups/GroupMembersModal.tsx
index a552e52d..208225e3 100644
--- a/web/src/features/groups/GroupMembersModal.tsx
+++ b/web/src/features/groups/GroupMembersModal.tsx
@@ -9,6 +9,7 @@ import { getFriends } from '@/lib/api/friends';
 import { canRemoveMember, getAllGroupMembers, inviteGroupMembers, removeGroupMember, type GroupInvitationResult, type GroupRole } from '@/lib/api/groups';
 import { avatarBgClass, avatarLetter } from '@/lib/avatar';
 import { useEscapeKey } from '@/lib/hooks';
+import { groupMemberDisplayName } from '@/lib/messages/group-member-name';
 import { requestConfirm } from '@/stores/confirmDialog';
 import { openUserCard } from '@/stores/userCard';
 
@@ -81,7 +82,7 @@ export function GroupMembersModal({ topicId, canInvite, myUserId, myRole, initia
 
   const membersQuery = useQuery({ queryKey: ['group-members', topicId], queryFn: () => getAllGroupMembers(topicId) });
   const members = membersQuery.data || [];
-  const filtered = members.filter((m) => !query.trim() || (m.display_name || m.user_id).toLowerCase().includes(query.trim().toLowerCase()));
+  const filtered = members.filter((m) => !query.trim() || groupMemberDisplayName(m).toLowerCase().includes(query.trim().toLowerCase()));
 
   const friendsQuery = useQuery({
     queryKey: ['friends'],
@@ -198,9 +199,9 @@ export function GroupMembersModal({ topicId, canInvite, myUserId, myRole, initia
               <div key={m.user_id} className="flex w-full items-center gap-3 rounded-lg px-3 py-2">
                 <button type="button" onClick={() => openUserCard(m.user_id)} className="flex min-w-0 flex-1 items-center gap-3 text-left">
                   <span className={`grid h-9 w-9 flex-none place-items-center rounded-lg text-sm font-medium text-white ${avatarBgClass(m.user_id)}`}>
-                    {avatarLetter(m.display_name)}
+                    {avatarLetter(groupMemberDisplayName(m))}
                   </span>
-                  <span className="min-w-0 flex-1 truncate text-sm text-text-body">{m.display_name || m.user_id}</span>
+                  <span className="min-w-0 flex-1 truncate text-sm text-text-body">{groupMemberDisplayName(m)}</span>
                 </button>
                 <RoleTag role={m.role} />
                 {canRemoveMember(myUserId, myRole, m) ? (
@@ -208,7 +209,7 @@ export function GroupMembersModal({ topicId, canInvite, myUserId, myRole, initia
                     type="button"
                     disabled={removingIds.has(m.user_id)}
                     onClick={async () => {
-                      const label = m.display_name || m.user_id;
+                      const label = groupMemberDisplayName(m);
                       if (await requestConfirm({ message: `确定将"${label}"移出群聊吗？`, danger: true })) {
                         setRemovingIds((prev) => new Set(prev).add(m.user_id));
                         removeMutation.mutate(m.user_id, {
diff --git a/web/src/features/messages/ConversationView.tsx b/web/src/features/messages/ConversationView.tsx
index 08261b4f..87312a2d 100644
--- a/web/src/features/messages/ConversationView.tsx
+++ b/web/src/features/messages/ConversationView.tsx
@@ -28,6 +28,7 @@ import { flatTextContentOf, isRecalled } from '@/lib/messages/dispatch';
 import { buildMentionedContent, detectMentionTrigger, type PendingMention } from '@/lib/messages/mentions';
 import { buildReplyInfo, replySnapshotText } from '@/lib/messages/reply';
 import { groupSenderLabel } from '@/lib/messages/sender-name';
+import { groupMemberDisplayName } from '@/lib/messages/group-member-name';
 import { sendFile, sendImage, sendVoice } from '@/lib/tinode/attachments';
 import { isTopicGone } from '@/lib/tinode/errors';
 import { useChatList, useTinode, useTopicMessages } from '@/lib/tinode/hooks';
@@ -602,7 +603,8 @@ export function ConversationView() {
   const quotedSenderLabel = (fromUserId: string | undefined) => {
     if (myUserId && fromUserId === myUserId) return '我';
     if (isGroup && fromUserId) {
-      return groupSenderLabel(memberByUserId.get(fromUserId)?.display_name, staleSenderById.get(fromUserId)?.display_name);
+      const member = memberByUserId.get(fromUserId);
+      return groupSenderLabel(member && groupMemberDisplayName(member), staleSenderById.get(fromUserId)?.display_name);
     }
     return peerName;
   };
@@ -1075,7 +1077,7 @@ export function ConversationView() {
               mine={mine}
               isGroup={isGroup}
               peerName={peerName}
-              senderName={sender?.display_name || staleSender?.display_name}
+              senderName={sender ? groupMemberDisplayName(sender) : staleSender?.display_name}
               senderRole={sender?.role}
               avatarFileId={rowAvatarFileId}
               selectMode={selectMode}
diff --git a/web/src/features/messages/HistorySearchModal.tsx b/web/src/features/messages/HistorySearchModal.tsx
index 9bb375e4..eb63a5eb 100644
--- a/web/src/features/messages/HistorySearchModal.tsx
+++ b/web/src/features/messages/HistorySearchModal.tsx
@@ -11,6 +11,7 @@ import { useAuthedBlobUrl, useDebouncedValue, useEscapeKey } from '@/lib/hooks';
 import { contactCardContentOf, mobileAttachmentContentOf } from '@/lib/messages/dispatch';
 import { renderDrafty } from '@/lib/messages/drafty';
 import { groupSenderLabel } from '@/lib/messages/sender-name';
+import { groupMemberDisplayName } from '@/lib/messages/group-member-name';
 import { formatEventTimestamp } from '@/lib/messages/time';
 import { requestConfirm } from '@/stores/confirmDialog';
 import { notify } from '@/stores/globalToast';
@@ -199,7 +200,10 @@ export function HistorySearchModal({ topicId, initialTab = 'text', onClose, isGr
   const senderLabel = (from: string): string => {
     const full = normalizeSender(from);
     if (myUserId && full === myUserId) return '我';
-    if (isGroup) return groupSenderLabel(membersQuery.data?.find((m) => m.user_id === full)?.display_name);
+    if (isGroup) {
+      const member = membersQuery.data?.find((m) => m.user_id === full);
+      return groupSenderLabel(member && groupMemberDisplayName(member));
+    }
     return peerName;
   };
 
diff --git a/web/src/features/messages/MentionPicker.tsx b/web/src/features/messages/MentionPicker.tsx
index c1a2983e..ac180af1 100644
--- a/web/src/features/messages/MentionPicker.tsx
+++ b/web/src/features/messages/MentionPicker.tsx
@@ -58,7 +58,7 @@ export function MentionPicker({ topicId, query, onPick }: MentionPickerProps) {
             // who have no idea what the sender's personal remark for this person means. `nickname`
             // is that member's own real public name, unaffected by anyone's remark, so it stays
             // correct for whoever else ends up reading the mention.
-            const label = m.nickname || m.display_name || m.user_id;
+            const label = m.group_nickname || m.nickname || m.display_name || m.user_id;
             return (
               <button
                 key={m.user_id}
diff --git a/web/src/lib/api/groups.ts b/web/src/lib/api/groups.ts
index af1aef90..ca230e5e 100644
--- a/web/src/lib/api/groups.ts
+++ b/web/src/lib/api/groups.ts
@@ -159,6 +159,8 @@ export interface GroupMember {
    * OTHER member then saw with no idea who it meant. Use `nickname` (below) instead for that case.
    */
   display_name?: string;
+  /** Name chosen by this member for this group. */
+  group_nickname?: string;
   /** The member's own real public profile nickname -- same backend response, but from
    *  copyUserNickname(), which reads straight off their public profile and is NEVER shadowed by the
    *  viewer's own remark the way `display_name` above is. This is what stays correct for everyone
@@ -176,7 +178,6 @@ export interface GroupMember {
   acs?: { want?: string; given?: string; mode?: string };
 }
 
-/** `GET .../members` never returns `group_nickname` on any item. */
 export function getGroupMembers(
   topic: string,
   opts: { query?: string; cursor?: string; role?: GroupRole; eligibleRole?: 'admin' | 'owner'; mentionable?: boolean; muteEligible?: boolean } = {},
diff --git a/web/src/lib/messages/group-member-name.ts b/web/src/lib/messages/group-member-name.ts
new file mode 100644
index 00000000..30248d51
--- /dev/null
+++ b/web/src/lib/messages/group-member-name.ts
@@ -0,0 +1,9 @@
+type GroupMemberName = {
+  group_nickname?: string;
+  display_name?: string;
+  user_id: string;
+};
+
+export function groupMemberDisplayName(member: GroupMemberName): string {
+  return member.group_nickname?.trim() || member.display_name?.trim() || member.user_id;
+}
diff --git a/web/src/lib/tinode/topics.ts b/web/src/lib/tinode/topics.ts
index f7cf3616..3cc75401 100644
--- a/web/src/lib/tinode/topics.ts
+++ b/web/src/lib/tinode/topics.ts
@@ -185,7 +185,7 @@ export function subscribeAnyTopicChange(callback: () => void): () => void {
 }
 
 export interface RawTopicInfo {
-  what: 'read' | 'recv' | 'kp' | 'call' | 'im';
+  what: 'read' | 'recv' | 'kp' | 'call' | 'im' | 'group';
   seq?: number;
   from?: string;
   event?: string;
diff --git a/web/tests/group-member-name.test.ts b/web/tests/group-member-name.test.ts
new file mode 100644
index 00000000..9a912fe0
--- /dev/null
+++ b/web/tests/group-member-name.test.ts
@@ -0,0 +1,13 @@
+import assert from 'node:assert/strict';
+import test from 'node:test';
+
+import { groupMemberDisplayName } from '../src/lib/messages/group-member-name.ts';
+
+test('group nickname wins over a viewer remark or public nickname', () => {
+  assert.equal(groupMemberDisplayName({ user_id: 'usrA', group_nickname: '群里小王', display_name: '好友备注' }), '群里小王');
+});
+
+test('empty group nickname falls back to the usual member name', () => {
+  assert.equal(groupMemberDisplayName({ user_id: 'usrA', group_nickname: ' ', display_name: '公开昵称' }), '公开昵称');
+  assert.equal(groupMemberDisplayName({ user_id: 'usrA' }), 'usrA');
+});