diff --git a/apps/web-antd/src/api/core/im.ts b/apps/web-antd/src/api/core/im.ts
index 04cfe5d..fb453fc 100644
--- a/apps/web-antd/src/api/core/im.ts
+++ b/apps/web-antd/src/api/core/im.ts
@@ -1,6 +1,8 @@
 import { RequestClient } from '@vben/request';
 import { useAccessStore } from '@vben/stores';
 
+import { requestClient } from '#/api/request';
+
 const imRequestClient = new RequestClient({
   baseURL: 'http://localhost:5212/api',
 });
@@ -29,14 +31,14 @@ export namespace ImApi {
   export interface Conversation {
     id: string;
     type: number;
-    lastMessageContent: string | null;
-    lastMessageAt: string | null;
+    lastMessageContent: null | string;
+    lastMessageAt: null | string;
     unreadCount: number;
-    groupName: string | null;
-    groupAvatar: string | null;
-    otherUserId: string | null;
-    otherUserName: string | null;
-    otherUserAvatar: string | null;
+    groupName: null | string;
+    groupAvatar: null | string;
+    otherUserId: null | string;
+    otherUserName: null | string;
+    otherUserAvatar: null | string;
   }
 
   export interface Message {
@@ -44,22 +46,22 @@ export namespace ImApi {
     conversationId: string;
     senderId: string;
     senderName: string;
-    senderAvatar: string | null;
+    senderAvatar: null | string;
     contentType: number;
     content: string;
     metadata: MessageMetadata | null;
-    replyToId: string | null;
+    replyToId: null | string;
     createdAt: string;
   }
 
   export interface MessageMetadata {
-    fileName?: string | null;
-    fileSize?: number | null;
-    fileUrl?: string | null;
-    imageUrl?: string | null;
-    imageWidth?: number | null;
-    imageHeight?: number | null;
-    emojiCode?: string | null;
+    fileName?: null | string;
+    fileSize?: null | number;
+    fileUrl?: null | string;
+    imageUrl?: null | string;
+    imageWidth?: null | number;
+    imageHeight?: null | number;
+    emojiCode?: null | string;
   }
 
   export interface MessageHistory {
@@ -76,8 +78,8 @@ export namespace ImApi {
     id: string;
     conversationId: string;
     name: string;
-    avatar: string | null;
-    description: string | null;
+    avatar: null | string;
+    description: null | string;
     ownerId: string;
     memberCount: number;
     createdAt: string;
@@ -86,10 +88,19 @@ export namespace ImApi {
   export interface GroupMember {
     userId: string;
     userName: string;
-    avatar: string | null;
+    avatar: null | string;
     role: number;
     joinedAt: string;
   }
+
+  export interface User {
+    id: string;
+    username: string;
+    email: string;
+    isActive: boolean;
+    createdAt: string;
+    roles: string[];
+  }
 }
 
 export async function getConversationsApi() {
@@ -114,17 +125,17 @@ export async function getUnreadCountApi() {
 }
 
 export async function createGroupApi(data: {
-  name: string;
   avatar?: string;
   description?: string;
   memberUserIds: string[];
+  name: string;
 }) {
   return imRequestClient.post<ImApi.GroupInfo>('/groups', data);
 }
 
 export async function updateGroupApi(
   groupId: string,
-  data: { name?: string; avatar?: string; description?: string },
+  data: { avatar?: string; description?: string; name?: string; },
 ) {
   return imRequestClient.put<ImApi.GroupInfo>(`/groups/${groupId}`, data);
 }
@@ -144,3 +155,17 @@ export async function removeGroupMemberApi(groupId: string, userId: string) {
 export async function getGroupMembersApi(groupId: string) {
   return imRequestClient.get<ImApi.GroupMember[]>(`/groups/${groupId}/members`);
 }
+
+// 用户搜索 — 直连 rag-backend
+export async function searchUsersApi(search?: string) {
+  const params: Record<string, any> = {};
+  if (search) params.search = search;
+  return requestClient.get<ImApi.User[]>('/users', { params });
+}
+
+// 创建或获取私聊会话 — IM 后端
+export async function createPrivateConversationApi(targetUserId: string) {
+  return imRequestClient.post<ImApi.Conversation>('/conversations/private', {
+    targetUserId,
+  });
+}
diff --git a/apps/web-antd/src/store/im.ts b/apps/web-antd/src/store/im.ts
index 8c4fc59..b40317e 100644
--- a/apps/web-antd/src/store/im.ts
+++ b/apps/web-antd/src/store/im.ts
@@ -1,23 +1,30 @@
-import { ref, computed } from 'vue';
-import { defineStore } from 'pinia';
-
 import type { ImApi } from '#/api/core/im';
 
+import { computed, ref } from 'vue';
+
+import { useUserStore } from '@vben/stores';
+
+import { defineStore } from 'pinia';
+
 import {
+  createPrivateConversationApi,
   getConversationsApi,
   getMessageHistoryApi,
   getUnreadCountApi,
+  searchUsersApi,
 } from '#/api/core/im';
 import { signalRService } from '#/api/core/signalr';
 
 export const useImStore = defineStore('im', () => {
   const conversations = ref<ImApi.Conversation[]>([]);
-  const activeConversationId = ref<string | null>(null);
+  const activeConversationId = ref<null | string>(null);
   const messages = ref<Map<string, ImApi.Message[]>>(new Map());
   const unreadCounts = ref<Map<string, number>>(new Map());
   const onlineUsers = ref<Set<string>>(new Set());
   const connected = ref(false);
   const typingUsers = ref<Map<string, Set<string>>>(new Map());
+  const contacts = ref<ImApi.User[]>([]);
+  const contactsLoading = ref(false);
 
   const totalUnread = computed(() => {
     let total = 0;
@@ -50,7 +57,7 @@ export const useImStore = defineStore('im', () => {
       if (conv) {
         conv.lastMessageContent =
           message.contentType === 0
-            ? message.content.substring(0, 50)
+            ? message.content.slice(0, 50)
             : `[${['文本', '图片', '文件', '系统', '表情'][message.contentType] || '消息'}]`;
         conv.lastMessageAt = message.createdAt;
       }
@@ -145,10 +152,31 @@ export const useImStore = defineStore('im', () => {
     await signalRService.typing(conversationId);
   }
 
-  function setActiveConversation(conversationId: string | null) {
+  function setActiveConversation(conversationId: null | string) {
     activeConversationId.value = conversationId;
   }
 
+  async function searchContacts(query?: string) {
+    contactsLoading.value = true;
+    try {
+      const userStore = useUserStore();
+      const data = await searchUsersApi(query);
+      contacts.value = data.filter(
+        (u) => u.id !== userStore.userInfo?.userId,
+      );
+    } finally {
+      contactsLoading.value = false;
+    }
+  }
+
+  async function startPrivateChat(targetUserId: string) {
+    const conversation = await createPrivateConversationApi(targetUserId);
+    await loadConversations();
+    setActiveConversation(conversation.id);
+    await loadMessages(conversation.id);
+    return conversation;
+  }
+
   return {
     // State
     conversations,
@@ -158,6 +186,8 @@ export const useImStore = defineStore('im', () => {
     onlineUsers,
     connected,
     typingUsers,
+    contacts,
+    contactsLoading,
     // Computed
     totalUnread,
     activeMessages,
@@ -172,5 +202,7 @@ export const useImStore = defineStore('im', () => {
     markAsRead,
     typing,
     setActiveConversation,
+    searchContacts,
+    startPrivateChat,
   };
 });
diff --git a/apps/web-antd/src/views/im/index.vue b/apps/web-antd/src/views/im/index.vue
index a953b73..26627c9 100644
--- a/apps/web-antd/src/views/im/index.vue
+++ b/apps/web-antd/src/views/im/index.vue
@@ -1,4 +1,6 @@
 <script setup lang="ts">
+import type { ImApi } from '#/api/core/im';
+
 import { computed, nextTick, onMounted, onUnmounted, ref } from 'vue';
 
 import { useUserStore } from '@vben/stores';
@@ -17,8 +19,15 @@ const showCreateGroup = ref(false);
 const showGroupManage = ref(false);
 const newGroupName = ref('');
 const newGroupDesc = ref('');
+const selectedMemberIds = ref<string[]>([]);
+const memberSearchLoading = ref(false);
 const messageListRef = ref<HTMLElement | null>(null);
 
+// Sidebar tab
+const sidebarTab = ref<'contacts' | 'messages'>('messages');
+const contactSearchQuery = ref('');
+let contactSearchTimer: ReturnType<typeof setTimeout> | null = null;
+
 const activeConversationId = computed(() => imStore.activeConversationId);
 const activeConversation = computed(() => imStore.activeConversation);
 const activeMessages = computed(() => imStore.activeMessages);
@@ -31,7 +40,7 @@ const sortedConversations = computed(() =>
   }),
 );
 
-function isSelfMessage(msg: any) {
+function isSelfMessage(msg: ImApi.Message) {
   return msg.senderId === userStore.userInfo?.userId;
 }
 
@@ -84,6 +93,17 @@ async function handleSend(e?: any) {
   }
 }
 
+async function handleStartChat(user: ImApi.User) {
+  try {
+    await imStore.startPrivateChat(user.id);
+    sidebarTab.value = 'messages';
+    await nextTick();
+    scrollToBottom();
+  } catch {
+    message.error('创建会话失败');
+  }
+}
+
 async function handleCreateGroup() {
   if (!newGroupName.value.trim()) {
     message.warning('请输入群名称');
@@ -93,18 +113,33 @@ async function handleCreateGroup() {
     await createGroupApi({
       name: newGroupName.value,
       description: newGroupDesc.value || undefined,
-      memberUserIds: [],
+      memberUserIds: selectedMemberIds.value,
     });
     message.success('群聊创建成功');
     showCreateGroup.value = false;
     newGroupName.value = '';
     newGroupDesc.value = '';
+    selectedMemberIds.value = [];
     await imStore.loadConversations();
   } catch {
     message.error('创建失败');
   }
 }
 
+function handleContactSearch() {
+  if (contactSearchTimer) clearTimeout(contactSearchTimer);
+  contactSearchTimer = setTimeout(() => {
+    imStore.searchContacts(contactSearchQuery.value || undefined);
+  }, 300);
+}
+
+function handleMemberSearch(value: string) {
+  memberSearchLoading.value = true;
+  imStore.searchContacts(value || undefined).finally(() => {
+    memberSearchLoading.value = false;
+  });
+}
+
 function scrollToBottom() {
   if (messageListRef.value) {
     messageListRef.value.scrollTop = messageListRef.value.scrollHeight;
@@ -122,6 +157,11 @@ async function onScroll() {
   }
 }
 
+function switchToContacts() {
+  sidebarTab.value = 'contacts';
+  imStore.searchContacts();
+}
+
 onMounted(async () => {
   await imStore.connect();
   await imStore.loadConversations();
@@ -138,57 +178,134 @@ onUnmounted(() => {
     class="flex h-[calc(100vh-120px)] overflow-hidden rounded-lg border border-border bg-card"
   >
     <!-- Sidebar -->
-    <div
-      class="flex w-[300px] shrink-0 flex-col border-r border-border"
-    >
-      <div
-        class="flex items-center justify-between border-b border-border px-4 py-3"
-      >
-        <h3 class="m-0 p-0 text-base font-medium text-foreground">消息</h3>
-        <a-button type="primary" size="small" @click="showCreateGroup = true">
-          创建群聊
-        </a-button>
-      </div>
-
-      <div class="flex-1 overflow-y-auto">
+    <div class="flex w-[300px] shrink-0 flex-col border-r border-border">
+      <!-- Tabs -->
+      <div class="flex border-b border-border">
         <div
-          v-for="conv in sortedConversations"
-          :key="conv.id"
-          class="flex cursor-pointer items-center px-4 py-3 transition-colors hover:bg-accent"
-          :class="{
-            'bg-primary/10 dark:bg-accent': conv.id === activeConversationId,
-          }"
-          @click="selectConversation(conv.id)"
+          class="flex-1 cursor-pointer px-4 py-3 text-center text-sm transition-colors"
+          :class="
+            sidebarTab === 'messages'
+              ? 'border-b-2 border-primary font-medium text-foreground'
+              : 'text-muted-foreground hover:text-foreground'
+          "
+          @click="sidebarTab = 'messages'"
         >
-          <a-avatar v-if="conv.type === 2" :size="40">
-            {{ conv.groupName?.charAt(0) || '群' }}
-          </a-avatar>
-          <a-avatar v-else :size="40">
-            {{ conv.otherUserName?.charAt(0) || 'U' }}
-          </a-avatar>
-
-          <div class="ml-3 flex-1 overflow-hidden">
-            <div
-              class="truncate text-sm font-medium text-foreground"
-            >
-              {{
-                conv.type === 2
-                  ? conv.groupName
-                  : conv.otherUserName || '私聊'
-              }}
-            </div>
-            <div class="mt-1 truncate text-xs text-muted-foreground">
-              {{ conv.lastMessageContent || '暂无消息' }}
-            </div>
-          </div>
-
-          <a-badge
-            v-if="conv.unreadCount > 0"
-            :count="conv.unreadCount"
-            :overflow-count="99"
-          />
+          消息
+        </div>
+        <div
+          class="flex-1 cursor-pointer px-4 py-3 text-center text-sm transition-colors"
+          :class="
+            sidebarTab === 'contacts'
+              ? 'border-b-2 border-primary font-medium text-foreground'
+              : 'text-muted-foreground hover:text-foreground'
+          "
+          @click="switchToContacts"
+        >
+          通讯录
         </div>
       </div>
+
+      <!-- Messages panel -->
+      <template v-if="sidebarTab === 'messages'">
+        <div
+          class="flex items-center justify-between border-b border-border px-4 py-2"
+        >
+          <span class="text-sm text-muted-foreground">
+            {{ sortedConversations.length }} 个会话
+          </span>
+          <a-button
+            type="primary"
+            size="small"
+            @click="showCreateGroup = true"
+          >
+            创建群聊
+          </a-button>
+        </div>
+        <div class="flex-1 overflow-y-auto">
+          <div
+            v-for="conv in sortedConversations"
+            :key="conv.id"
+            class="flex cursor-pointer items-center px-4 py-3 transition-colors hover:bg-accent"
+            :class="{
+              'bg-primary/10 dark:bg-accent':
+                conv.id === activeConversationId,
+            }"
+            @click="selectConversation(conv.id)"
+          >
+            <a-avatar v-if="conv.type === 2" :size="40">
+              {{ conv.groupName?.charAt(0) || '群' }}
+            </a-avatar>
+            <a-avatar v-else :size="40">
+              {{ conv.otherUserName?.charAt(0) || 'U' }}
+            </a-avatar>
+
+            <div class="ml-3 flex-1 overflow-hidden">
+              <div class="truncate text-sm font-medium text-foreground">
+                {{
+                  conv.type === 2
+                    ? conv.groupName
+                    : conv.otherUserName || '私聊'
+                }}
+              </div>
+              <div class="mt-1 truncate text-xs text-muted-foreground">
+                {{ conv.lastMessageContent || '暂无消息' }}
+              </div>
+            </div>
+
+            <a-badge
+              v-if="conv.unreadCount > 0"
+              :count="conv.unreadCount"
+              :overflow-count="99"
+            />
+          </div>
+        </div>
+      </template>
+
+      <!-- Contacts panel -->
+      <template v-else>
+        <div class="border-b border-border px-3 py-2">
+          <a-input-search
+            v-model:value="contactSearchQuery"
+            placeholder="搜索用户名或邮箱"
+            @search="imStore.searchContacts(contactSearchQuery || undefined)"
+            @change="handleContactSearch"
+          />
+        </div>
+        <div class="flex-1 overflow-y-auto">
+          <a-spin :spinning="imStore.contactsLoading">
+            <div
+              v-for="user in imStore.contacts"
+              :key="user.id"
+              class="flex cursor-pointer items-center px-4 py-3 transition-colors hover:bg-accent"
+              @click="handleStartChat(user)"
+            >
+              <a-avatar :size="40">
+                {{ user.username.charAt(0).toUpperCase() }}
+              </a-avatar>
+              <div class="ml-3 flex-1 overflow-hidden">
+                <div class="truncate text-sm font-medium text-foreground">
+                  {{ user.username }}
+                </div>
+                <div class="mt-1 truncate text-xs text-muted-foreground">
+                  {{ user.email }}
+                </div>
+              </div>
+              <span
+                v-if="imStore.onlineUsers.has(user.id)"
+                class="mr-2 inline-block h-2 w-2 rounded-full bg-green-500"
+              />
+            </div>
+            <div
+              v-if="
+                !imStore.contactsLoading && imStore.contacts.length === 0
+              "
+              class="px-4 py-8 text-center text-sm text-muted-foreground"
+            >
+              没有找到用户
+            </div>
+          </a-spin>
+        </div>
+      </template>
     </div>
 
     <!-- Main chat area -->
@@ -259,9 +376,7 @@ onUnmounted(() => {
           </div>
         </div>
 
-        <div
-          class="flex gap-2 border-t border-border px-4 py-3"
-        >
+        <div class="flex gap-2 border-t border-border px-4 py-3">
           <a-textarea
             v-model:value="inputMessage"
             placeholder="输入消息..."
@@ -295,6 +410,24 @@ onUnmounted(() => {
         <a-form-item label="群描述">
           <a-input v-model:value="newGroupDesc" />
         </a-form-item>
+        <a-form-item label="选择成员">
+          <a-select
+            v-model:value="selectedMemberIds"
+            mode="multiple"
+            placeholder="搜索并选择成员"
+            :filter-option="false"
+            :loading="memberSearchLoading"
+            @search="handleMemberSearch"
+          >
+            <a-select-option
+              v-for="user in imStore.contacts"
+              :key="user.id"
+              :value="user.id"
+            >
+              {{ user.username }} ({{ user.email }})
+            </a-select-option>
+          </a-select>
+        </a-form-item>
       </a-form>
     </a-modal>
   </div>