diff --git a/system1-factory/web/js/vacation-allocation.js b/system1-factory/web/js/vacation-allocation.js
index 6bfe907..06e81c1 100644
--- a/system1-factory/web/js/vacation-allocation.js
+++ b/system1-factory/web/js/vacation-allocation.js
@@ -77,13 +77,25 @@ async function loadWorkers() {
       return;
     }
 
-    // 개별 입력 탭 - 작업자 셀렉트 박스
+    // 개별 입력 탭 - 작업자 셀렉트 박스 (부서별 그룹)
     const selectWorker = document.getElementById('individualWorker');
+    const byDept = {};
     workers.forEach(worker => {
-      const option = document.createElement('option');
-      option.value = worker.user_id;
-      option.textContent = `${worker.worker_name} (${worker.employment_status === 'employed' ? '재직' : '퇴사'})`;
-      selectWorker.appendChild(option);
+      const dept = worker.department_name || '부서 미지정';
+      if (!byDept[dept]) byDept[dept] = [];
+      byDept[dept].push(worker);
+    });
+
+    Object.keys(byDept).sort().forEach(dept => {
+      const group = document.createElement('optgroup');
+      group.label = dept;
+      byDept[dept].forEach(worker => {
+        const option = document.createElement('option');
+        option.value = worker.user_id;
+        option.textContent = `${worker.worker_name} (${worker.employment_status === 'employed' ? '재직' : '퇴사'})`;
+        group.appendChild(option);
+      });
+      selectWorker.appendChild(group);
     });
     console.log(`Loaded ${workers.length} workers successfully`);
   } catch (error) {
diff --git a/user-management/api/controllers/departmentController.js b/user-management/api/controllers/departmentController.js
index ebe7ad5..4471acb 100644
--- a/user-management/api/controllers/departmentController.js
+++ b/user-management/api/controllers/departmentController.js
@@ -56,8 +56,8 @@ async function update(req, res, next) {
 async function remove(req, res, next) {
   try {
     const id = parseInt(req.params.id);
-    await departmentModel.deactivate(id);
-    res.json({ success: true, message: '부서가 비활성화되었습니다' });
+    await departmentModel.remove(id);
+    res.json({ success: true, message: '부서가 삭제되었습니다' });
   } catch (err) {
     next(err);
   }
diff --git a/user-management/api/models/departmentModel.js b/user-management/api/models/departmentModel.js
index 40c2a5b..32e3486 100644
--- a/user-management/api/models/departmentModel.js
+++ b/user-management/api/models/departmentModel.js
@@ -9,9 +9,8 @@ const { getPool } = require('./userModel');
 async function getAll() {
   const db = getPool();
   const [rows] = await db.query(
-    `SELECT d.*, p.department_name AS parent_name
+    `SELECT d.*
      FROM departments d
-     LEFT JOIN departments p ON d.parent_id = p.department_id
      ORDER BY d.display_order ASC, d.department_id ASC`
   );
   return rows;
@@ -20,21 +19,20 @@ async function getAll() {
 async function getById(id) {
   const db = getPool();
   const [rows] = await db.query(
-    `SELECT d.*, p.department_name AS parent_name
+    `SELECT d.*
      FROM departments d
-     LEFT JOIN departments p ON d.parent_id = p.department_id
      WHERE d.department_id = ?`,
     [id]
   );
   return rows[0] || null;
 }
 
-async function create({ department_name, parent_id, description, display_order }) {
+async function create({ department_name, description, display_order }) {
   const db = getPool();
   const [result] = await db.query(
-    `INSERT INTO departments (department_name, parent_id, description, display_order)
-     VALUES (?, ?, ?, ?)`,
-    [department_name, parent_id || null, description || null, display_order || 0]
+    `INSERT INTO departments (department_name, description, display_order)
+     VALUES (?, ?, ?)`,
+    [department_name, description || null, display_order || 0]
   );
   return getById(result.insertId);
 }
@@ -45,9 +43,7 @@ async function update(id, data) {
   const values = [];
 
   if (data.department_name !== undefined) { fields.push('department_name = ?'); values.push(data.department_name); }
-  if (data.parent_id !== undefined) { fields.push('parent_id = ?'); values.push(data.parent_id || null); }
   if (data.description !== undefined) { fields.push('description = ?'); values.push(data.description || null); }
-  if (data.is_active !== undefined) { fields.push('is_active = ?'); values.push(data.is_active); }
   if (data.display_order !== undefined) { fields.push('display_order = ?'); values.push(data.display_order); }
 
   if (fields.length === 0) return getById(id);
@@ -60,12 +56,20 @@ async function update(id, data) {
   return getById(id);
 }
 
-async function deactivate(id) {
+async function remove(id) {
   const db = getPool();
-  await db.query(
-    'UPDATE departments SET is_active = FALSE WHERE department_id = ?',
-    [id]
-  );
+  const conn = await db.getConnection();
+  try {
+    await conn.beginTransaction();
+    await conn.query('UPDATE users SET department_id = NULL WHERE department_id = ?', [id]);
+    await conn.query('DELETE FROM departments WHERE department_id = ?', [id]);
+    await conn.commit();
+  } catch (e) {
+    await conn.rollback();
+    throw e;
+  } finally {
+    conn.release();
+  }
 }
 
-module.exports = { getAll, getById, create, update, deactivate };
+module.exports = { getAll, getById, create, update, remove };
diff --git a/user-management/web/index.html b/user-management/web/index.html
index f30c8e1..e2cc492 100644
--- a/user-management/web/index.html
+++ b/user-management/web/index.html
@@ -465,12 +465,6 @@
                             <label class="block text-xs font-medium text-gray-600 mb-1">부서명 <span class="text-red-400">*</span></label>
                             <input type="text" id="newDeptName" class="input-field w-full px-3 py-1.5 rounded-lg text-sm" placeholder="부서 이름" required>
                         </div>
-                        <div>
-                            <label class="block text-xs font-medium text-gray-600 mb-1">상위부서</label>
-                            <select id="newDeptParent" class="input-field w-full px-3 py-1.5 rounded-lg text-sm">
-                                <option value="">없음 (최상위)</option>
-                            </select>
-                        </div>
                         <div>
                             <label class="block text-xs font-medium text-gray-600 mb-1">설명</label>
                             <input type="text" id="newDeptDescription" class="input-field w-full px-3 py-1.5 rounded-lg text-sm" placeholder="부서 설명">
@@ -1087,28 +1081,13 @@
                     <label class="block text-xs font-medium text-gray-600 mb-1">부서명</label>
                     <input type="text" id="editDeptName" class="input-field w-full px-3 py-1.5 rounded-lg text-sm" required>
                 </div>
-                <div>
-                    <label class="block text-xs font-medium text-gray-600 mb-1">상위부서</label>
-                    <select id="editDeptParent" class="input-field w-full px-3 py-1.5 rounded-lg text-sm">
-                        <option value="">없음 (최상위)</option>
-                    </select>
-                </div>
                 <div>
                     <label class="block text-xs font-medium text-gray-600 mb-1">설명</label>
                     <input type="text" id="editDeptDescription" class="input-field w-full px-3 py-1.5 rounded-lg text-sm">
                 </div>
-                <div class="grid grid-cols-2 gap-3">
-                    <div>
-                        <label class="block text-xs font-medium text-gray-600 mb-1">표시순서</label>
-                        <input type="number" id="editDeptOrder" class="input-field w-full px-3 py-1.5 rounded-lg text-sm" min="0">
-                    </div>
-                    <div>
-                        <label class="block text-xs font-medium text-gray-600 mb-1">활성</label>
-                        <select id="editDeptActive" class="input-field w-full px-3 py-1.5 rounded-lg text-sm">
-                            <option value="1">활성</option>
-                            <option value="0">비활성</option>
-                        </select>
-                    </div>
+                <div>
+                    <label class="block text-xs font-medium text-gray-600 mb-1">표시순서</label>
+                    <input type="number" id="editDeptOrder" class="input-field w-full px-3 py-1.5 rounded-lg text-sm" min="0">
                 </div>
                 <div class="flex gap-3 pt-3">
                     <button type="button" onclick="closeDepartmentModal()" class="flex-1 px-4 py-2 border border-gray-300 rounded-lg hover:bg-gray-50 text-sm">취소</button>
diff --git a/user-management/web/static/js/tkuser-departments.js b/user-management/web/static/js/tkuser-departments.js
index cef1c76..fb4b6e4 100644
--- a/user-management/web/static/js/tkuser-departments.js
+++ b/user-management/web/static/js/tkuser-departments.js
@@ -5,25 +5,12 @@ async function loadDepartments() {
     try {
         const r = await api('/departments'); departments = r.data || r;
         departmentsLoaded = true;
-        populateParentDeptSelects();
         displayDepartments();
     } catch (err) {
         document.getElementById('departmentList').innerHTML = `<div class="text-red-500 text-center py-6"><i class="fas fa-exclamation-triangle text-xl"></i><p class="text-sm mt-2">${err.message}</p></div>`;
     }
 }
 
-function populateParentDeptSelects() {
-    ['newDeptParent','editDeptParent'].forEach(id => {
-        const sel = document.getElementById(id); if (!sel) return;
-        const val = sel.value;
-        sel.innerHTML = '<option value="">없음 (최상위)</option>';
-        departments.filter(d => d.is_active !== 0 && d.is_active !== false).forEach(d => {
-            const o = document.createElement('option'); o.value = d.department_id; o.textContent = d.department_name; sel.appendChild(o);
-        });
-        sel.value = val;
-    });
-}
-
 let selectedDeptForMembers = null;
 
 function displayDepartments() {
@@ -34,14 +21,12 @@ function displayDepartments() {
             <div class="flex-1 min-w-0">
                 <div class="text-sm font-medium text-gray-800 truncate"><i class="fas fa-sitemap mr-1.5 text-gray-400 text-xs"></i>${d.department_name}</div>
                 <div class="text-xs text-gray-500 flex items-center gap-1.5 mt-0.5 flex-wrap">
-                    ${d.parent_name ? `<span class="px-1.5 py-0.5 rounded bg-slate-50 text-slate-500">상위: ${d.parent_name}</span>` : '<span class="px-1.5 py-0.5 rounded bg-indigo-50 text-indigo-500">최상위</span>'}
                     <span class="text-gray-400">순서: ${d.display_order || 0}</span>
-                    ${d.is_active === 0 || d.is_active === false ? '<span class="px-1.5 py-0.5 rounded bg-gray-100 text-gray-400">비활성</span>' : '<span class="px-1.5 py-0.5 rounded bg-emerald-50 text-emerald-600">활성</span>'}
                 </div>
             </div>
             <div class="flex gap-1 ml-2 flex-shrink-0" onclick="event.stopPropagation()">
                 <button onclick="editDepartment(${d.department_id})" class="p-1.5 text-slate-500 hover:text-slate-700 hover:bg-slate-200 rounded" title="편집"><i class="fas fa-pen-to-square text-xs"></i></button>
-                ${d.is_active !== 0 && d.is_active !== false ? `<button onclick="deactivateDepartment(${d.department_id},'${(d.department_name||'').replace(/'/g,"\\'")}')" class="p-1.5 text-red-400 hover:text-red-600 hover:bg-red-100 rounded" title="비활성화"><i class="fas fa-ban text-xs"></i></button>` : ''}
+                <button onclick="deleteDepartment(${d.department_id},'${(d.department_name||'').replace(/'/g,"\\'")}')" class="p-1.5 text-red-400 hover:text-red-600 hover:bg-red-100 rounded" title="삭제"><i class="fas fa-trash text-xs"></i></button>
             </div>
         </div>`).join('');
 }
@@ -96,7 +81,6 @@ document.getElementById('addDepartmentForm').addEventListener('submit', async e
     try {
         await api('/departments', { method: 'POST', body: JSON.stringify({
             department_name: document.getElementById('newDeptName').value.trim(),
-            parent_id: document.getElementById('newDeptParent').value ? parseInt(document.getElementById('newDeptParent').value) : null,
             description: document.getElementById('newDeptDescription').value.trim() || null,
             display_order: parseInt(document.getElementById('newDeptOrder').value) || 0
         })});
@@ -110,9 +94,6 @@ function editDepartment(id) {
     document.getElementById('editDeptName').value = d.department_name;
     document.getElementById('editDeptDescription').value = d.description || '';
     document.getElementById('editDeptOrder').value = d.display_order || 0;
-    document.getElementById('editDeptActive').value = (d.is_active === 0 || d.is_active === false) ? '0' : '1';
-    populateParentDeptSelects();
-    document.getElementById('editDeptParent').value = d.parent_id || '';
     document.getElementById('editDepartmentModal').classList.remove('hidden');
 }
 function closeDepartmentModal() { document.getElementById('editDepartmentModal').classList.add('hidden'); }
@@ -122,17 +103,15 @@ document.getElementById('editDepartmentForm').addEventListener('submit', async e
     try {
         await api(`/departments/${document.getElementById('editDeptId').value}`, { method: 'PUT', body: JSON.stringify({
             department_name: document.getElementById('editDeptName').value.trim(),
-            parent_id: document.getElementById('editDeptParent').value ? parseInt(document.getElementById('editDeptParent').value) : null,
             description: document.getElementById('editDeptDescription').value.trim() || null,
-            display_order: parseInt(document.getElementById('editDeptOrder').value) || 0,
-            is_active: document.getElementById('editDeptActive').value === '1'
+            display_order: parseInt(document.getElementById('editDeptOrder').value) || 0
         })});
         showToast('수정되었습니다.'); closeDepartmentModal(); await loadDepartments();
         await loadDepartmentsForSelect();
     } catch(e) { showToast(e.message, 'error'); }
 });
 
-async function deactivateDepartment(id, name) {
-    if (!confirm(`"${name}" 부서를 비활성화?`)) return;
-    try { await api(`/departments/${id}`, { method: 'DELETE' }); showToast('부서 비활성화 완료'); await loadDepartments(); } catch(e) { showToast(e.message, 'error'); }
+async function deleteDepartment(id, name) {
+    if (!confirm(`"${name}" 부서를 삭제하시겠습니까? 소속 인원은 부서 미지정으로 변경됩니다.`)) return;
+    try { await api(`/departments/${id}`, { method: 'DELETE' }); showToast('부서가 삭제되었습니다'); await loadDepartments(); } catch(e) { showToast(e.message, 'error'); }
 }