diff --git a/backend/src/main/java/com/designhub/service/UserService.java b/backend/src/main/java/com/designhub/service/UserService.java
index 777be04..2ec61a9 100644
--- a/backend/src/main/java/com/designhub/service/UserService.java
+++ b/backend/src/main/java/com/designhub/service/UserService.java
@@ -508,8 +508,17 @@ public class UserService {
                 if (primaryDept != null) {
                     user.setDeptId(primaryDeptId);
                     user.setDeptName(primaryDept.getDeptName());
-                    // 根据主部门类型设置角色
-                    user.setRoleIds("receiving".equals(primaryDept.getDeptType()) ? "5" : "6");
+                    // 根据主部门类型设置角色（但如果用户已经是管理员，保留管理员角色）
+                    String currentRoleIds = user.getRoleIds();
+                    boolean isAdmin = currentRoleIds != null && 
+                                     (currentRoleIds.contains("1") || currentRoleIds.contains("2"));
+                    if (!isAdmin) {
+                        // 只有非管理员用户才根据部门类型设置角色
+                        user.setRoleIds("receiving".equals(primaryDept.getDeptType()) ? "5" : "6");
+                    } else {
+                        log.info("用户已是管理员，保留管理员角色: userId={}, roleIds={}", 
+                                user.getId(), currentRoleIds);
+                    }
                     user.setStatus(1); // 启用用户
                     needUpdate = true;
                     log.info("同步用户多个部门: userId={}, 部门数量={}, 主部门={}", 
@@ -530,7 +539,17 @@ public class UserService {
                     setUserDepartments(user.getId(), List.of(defaultDept.getId()), defaultDept.getId());
                     user.setDeptId(defaultDept.getId());
                     user.setDeptName(defaultDept.getDeptName());
-                    user.setRoleIds("receiving".equals(defaultDept.getDeptType()) ? "5" : "6");
+                    // 根据部门类型设置角色（但如果用户已经是管理员，保留管理员角色）
+                    String currentRoleIds = user.getRoleIds();
+                    boolean isAdmin = currentRoleIds != null && 
+                                     (currentRoleIds.contains("1") || currentRoleIds.contains("2"));
+                    if (!isAdmin) {
+                        // 只有非管理员用户才根据部门类型设置角色
+                        user.setRoleIds("receiving".equals(defaultDept.getDeptType()) ? "5" : "6");
+                    } else {
+                        log.info("用户已是管理员，保留管理员角色: userId={}, roleIds={}", 
+                                user.getId(), currentRoleIds);
+                    }
                     user.setStatus(1); // 启用用户
                     needUpdate = true;
                     log.warn("已有用户无法匹配，使用默认部门: userId={}, deptId={}, deptName={}, 钉钉部门: {}", 
diff --git a/frontend/src/views/Login.vue b/frontend/src/views/Login.vue
index 49106a2..9bd51f3 100644
--- a/frontend/src/views/Login.vue
+++ b/frontend/src/views/Login.vue
@@ -74,7 +74,7 @@
             </a-button>
           </a-form-item>
 
-          <div class="auth-switch">
+          <div v-if="registerEnabled" class="auth-switch">
             <span class="switch-text">还没有账号？</span>
             <button type="button" class="switch-link" @click="activeTab = 'register'">
               注册账号
@@ -226,12 +226,14 @@ import * as departmentApi from '@/api/department'
 import { isDingTalkFeatureEnabled } from '@/api/dingtalk'
 import request from '@/utils/request'
 import type { Result } from '@/api/types'
+import { getSystemConfig } from '@/api/system'
 
 const router = useRouter()
 const authStore = useAuthStore()
 const siteSettingsStore = useSiteSettingsStore()
 
 const activeTab = ref<'login' | 'register'>('login')
+const registerEnabled = ref(true)
 
 const loading = ref(false)
 const registerLoading = ref(false)
@@ -393,6 +395,22 @@ const checkDingTalkLogin = async () => {
   }
 }
 
+// 检查注册功能是否启用
+const checkRegisterEnabled = async () => {
+  try {
+    const response = await getSystemConfig('site.register.enabled')
+    if (response.data) {
+      registerEnabled.value = response.data === 'true' || response.data === '1'
+    } else {
+      registerEnabled.value = true // 默认开启
+    }
+    console.log('注册功能状态:', registerEnabled.value)
+  } catch (error) {
+    console.error('检查注册功能状态失败:', error)
+    registerEnabled.value = true // 默认开启
+  }
+}
+
 // 处理钉钉登录
 const handleDingTalkLogin = async () => {
   dingTalkLoginLoading.value = true
@@ -430,6 +448,9 @@ onMounted(() => {
   // 检查钉钉登录是否启用
   checkDingTalkLogin()
   
+  // 检查注册功能是否启用
+  checkRegisterEnabled()
+  
   // 监听网站设置更新事件（在加载后监听，确保能接收到事件）
   window.addEventListener('siteSettingsUpdated', handleSiteSettingsUpdate)
   
diff --git a/frontend/src/views/Settings.vue b/frontend/src/views/Settings.vue
index ca517c7..cef7ece 100644
--- a/frontend/src/views/Settings.vue
+++ b/frontend/src/views/Settings.vue
@@ -62,6 +62,18 @@
                   </div>
                 </a-form-item>
                 
+                <a-divider orientation="left">功能开关</a-divider>
+                <a-form-item label="注册功能">
+                  <a-switch
+                    v-model:checked="siteSettings.registerEnabled"
+                    checked-children="开启"
+                    un-checked-children="关闭"
+                  />
+                  <div style="margin-top: 8px; font-size: 12px; color: #888;">
+                    控制登录页面是否显示注册功能
+                  </div>
+                </a-form-item>
+                
                 <a-form-item>
                   <a-button type="primary" size="large" @click="handleSaveSiteSettings" :loading="savingSiteSettings">
                     <template #icon><Icon name="check" size="sm" /></template>
@@ -1384,8 +1396,10 @@ const router = useRouter()
 const siteSettings = reactive({
   siteName: 'DesignHub',
   logoUrl: '',
+  registerEnabled: true,
   siteNameConfigId: null as number | null,
-  logoConfigId: null as number | null
+  logoConfigId: null as number | null,
+  registerEnabledConfigId: null as number | null
 })
 
 const loading = reactive({
@@ -2519,11 +2533,21 @@ const loadSiteSettings = async () => {
     } else {
       siteSettings.logoUrl = siteSettingsStore.logoUrl
     }
+    
+    // 查找注册功能开关配置
+    const registerConfig = configs.find((c: any) => c.configKey === 'site.register.enabled')
+    if (registerConfig) {
+      siteSettings.registerEnabled = registerConfig.configValue === 'true' || registerConfig.configValue === '1'
+      siteSettings.registerEnabledConfigId = registerConfig.id
+    } else {
+      siteSettings.registerEnabled = true // 默认开启
+    }
   } catch (error) {
     console.error('加载网站设置失败:', error)
     // 如果API失败，尝试从store读取
     siteSettings.siteName = siteSettingsStore.siteName
     siteSettings.logoUrl = siteSettingsStore.logoUrl
+    siteSettings.registerEnabled = true // 默认开启
   } finally {
     loadingSiteSettings.value = false
   }
@@ -2599,6 +2623,29 @@ const handleSaveSiteSettings = async () => {
       }
     }
     
+    // 保存注册功能开关
+    if (siteSettings.registerEnabledConfigId) {
+      // 如果配置已存在，更新
+      await updateSystemConfig(siteSettings.registerEnabledConfigId, {
+        configValue: siteSettings.registerEnabled ? 'true' : 'false'
+      })
+    } else {
+      // 如果配置不存在，创建
+      const response = await createSystemConfig({
+        configKey: 'site.register.enabled',
+        configValue: siteSettings.registerEnabled ? 'true' : 'false',
+        configGroup: 'site',
+        configName: '注册功能开关',
+        description: '控制登录页面是否显示注册功能',
+        valueType: 'boolean',
+        builtIn: 0,
+        sortOrder: 3
+      })
+      if (response.data && response.data.id) {
+        siteSettings.registerEnabledConfigId = response.data.id
+      }
+    }
+    
     // 更新全局store（这会自动更新所有使用store的组件）
     siteSettingsStore.updateSiteSettings(siteSettings.siteName, siteSettings.logoUrl)