diff --git a/src/components/settings/AttendanceSettingsManagement/actions.ts b/src/components/settings/AttendanceSettingsManagement/actions.ts
index 3ef45697..78abc6a0 100644
--- a/src/components/settings/AttendanceSettingsManagement/actions.ts
+++ b/src/components/settings/AttendanceSettingsManagement/actions.ts
@@ -2,6 +2,8 @@
 
 import { serverFetch } from '@/lib/api/fetch-wrapper';
 
+const API_URL = process.env.NEXT_PUBLIC_API_URL;
+
 // ===== 타입 정의 =====
 
 // API 응답 타입
@@ -26,6 +28,28 @@ export interface AttendanceSettingFormData {
   hqLongitude: number | null;
 }
 
+// 부서 타입 (트리 구조 지원)
+export interface Department {
+  id: string;
+  name: string;
+  depth: number;
+}
+
+// API 부서 응답 타입
+interface ApiDepartment {
+  id: number;
+  name: string;
+  parent_id: number | null;
+  children?: ApiDepartment[];
+}
+
+// API 응답 공통 타입
+interface ApiResponse<T> {
+  success: boolean;
+  data?: T;
+  error?: string;
+}
+
 // ===== 데이터 변환 =====
 
 /**
@@ -61,30 +85,26 @@ function transformToApi(data: Partial<AttendanceSettingFormData>): Record<string
 /**
  * 출퇴근 설정 조회
  */
-export async function getAttendanceSetting(): Promise<{
-  success: boolean;
-  data?: AttendanceSettingFormData;
-  error?: string;
-}> {
+export async function getAttendanceSetting(): Promise<ApiResponse<AttendanceSettingFormData>> {
   try {
-    const headers = await getAuthHeaders();
-
-    const response = await fetch(`${API_BASE_URL}/api/v1/settings/attendance`, {
+    const { response, error } = await serverFetch(`${API_URL}/api/v1/settings/attendance`, {
       method: 'GET',
-      headers,
-      cache: 'no-store',
     });
 
-    if (!response.ok) {
-      const errorData = await response.json().catch(() => ({}));
-      return {
-        success: false,
-        error: errorData.message || `API 오류: ${response.status}`,
-      };
+    if (error) {
+      return { success: false, error: error.message };
+    }
+
+    if (!response) {
+      return { success: false, error: '출퇴근 설정 조회에 실패했습니다.' };
     }
 
     const result = await response.json();
 
+    if (!response.ok || !result.success) {
+      return { success: false, error: result.message || '출퇴근 설정 조회 실패' };
+    }
+
     return {
       success: true,
       data: transformFromApi(result.data),
@@ -103,30 +123,27 @@ export async function getAttendanceSetting(): Promise<{
  */
 export async function updateAttendanceSetting(
   data: Partial<AttendanceSettingFormData>
-): Promise<{
-  success: boolean;
-  data?: AttendanceSettingFormData;
-  error?: string;
-}> {
+): Promise<ApiResponse<AttendanceSettingFormData>> {
   try {
-    const headers = await getAuthHeaders();
-
-    const response = await fetch(`${API_BASE_URL}/api/v1/settings/attendance`, {
+    const { response, error } = await serverFetch(`${API_URL}/api/v1/settings/attendance`, {
       method: 'PUT',
-      headers,
       body: JSON.stringify(transformToApi(data)),
     });
 
-    if (!response.ok) {
-      const errorData = await response.json().catch(() => ({}));
-      return {
-        success: false,
-        error: errorData.message || `API 오류: ${response.status}`,
-      };
+    if (error) {
+      return { success: false, error: error.message };
+    }
+
+    if (!response) {
+      return { success: false, error: '출퇴근 설정 저장에 실패했습니다.' };
     }
 
     const result = await response.json();
 
+    if (!response.ok || !result.success) {
+      return { success: false, error: result.message || '출퇴근 설정 저장 실패' };
+    }
+
     return {
       success: true,
       data: transformFromApi(result.data),
@@ -138,4 +155,62 @@ export async function updateAttendanceSetting(
       error: '출퇴근 설정 저장에 실패했습니다.',
     };
   }
+}
+
+/**
+ * 트리 구조를 평탄화 (재귀)
+ */
+function flattenDepartmentTree(departments: ApiDepartment[], depth: number = 0): Department[] {
+  const result: Department[] = [];
+
+  for (const dept of departments) {
+    result.push({
+      id: String(dept.id),
+      name: dept.name,
+      depth,
+    });
+
+    if (dept.children && dept.children.length > 0) {
+      result.push(...flattenDepartmentTree(dept.children, depth + 1));
+    }
+  }
+
+  return result;
+}
+
+/**
+ * 부서 목록 조회 (트리 구조)
+ */
+export async function getDepartments(): Promise<ApiResponse<Department[]>> {
+  try {
+    // 트리 API 사용
+    const { response, error } = await serverFetch(`${API_URL}/api/v1/departments/tree`, {
+      method: 'GET',
+    });
+
+    if (error) {
+      return { success: false, error: error.message };
+    }
+
+    if (!response) {
+      return { success: false, error: '부서 목록 조회에 실패했습니다.' };
+    }
+
+    const result = await response.json();
+
+    if (!response.ok || !result.success) {
+      return { success: false, error: result.message || '부서 목록 조회 실패' };
+    }
+
+    // 트리를 평탄화하여 depth 포함된 배열로 변환
+    const departments = flattenDepartmentTree(result.data || []);
+
+    return { success: true, data: departments };
+  } catch (error) {
+    console.error('getDepartments error:', error);
+    return {
+      success: false,
+      error: '부서 목록을 불러오는데 실패했습니다.',
+    };
+  }
 }
\ No newline at end of file
diff --git a/src/components/settings/AttendanceSettingsManagement/index.tsx b/src/components/settings/AttendanceSettingsManagement/index.tsx
index 1b99fc01..e77625d8 100644
--- a/src/components/settings/AttendanceSettingsManagement/index.tsx
+++ b/src/components/settings/AttendanceSettingsManagement/index.tsx
@@ -150,10 +150,11 @@ export function AttendanceSettingsManagement() {
     }
   };
 
-  // 부서 옵션 변환
+  // 부서 옵션 변환 (depth 포함)
   const departmentOptions = departments.map(dept => ({
     value: dept.id,
     label: dept.name,
+    depth: dept.depth,
   }));
 
   // 선택된 부서 표시 텍스트
diff --git a/src/components/ui/multi-select-combobox.tsx b/src/components/ui/multi-select-combobox.tsx
index 33fb6564..7712243a 100644
--- a/src/components/ui/multi-select-combobox.tsx
+++ b/src/components/ui/multi-select-combobox.tsx
@@ -17,6 +17,7 @@ import { cn } from './utils';
 export interface MultiSelectOption {
   value: string;
   label: string;
+  depth?: number; // 트리 구조 들여쓰기용
 }
 
 interface MultiSelectComboboxProps {
@@ -107,14 +108,15 @@ export function MultiSelectCombobox({
                   value={option.label}
                   onSelect={() => handleSelect(option.value)}
                   className="cursor-pointer"
+                  style={{ paddingLeft: option.depth ? `${(option.depth * 16) + 8}px` : undefined }}
                 >
                   <Check
                     className={cn(
-                      'mr-2 h-4 w-4',
+                      'mr-2 h-4 w-4 shrink-0',
                       value.includes(option.value) ? 'opacity-100' : 'opacity-0'
                     )}
                   />
-                  {option.label}
+                  <span className="truncate">{option.label}</span>
                 </CommandItem>
               ))}
             </CommandGroup>