diff --git a/apps/backend/src/db/migrations/061_work_order_admin_note.sql b/apps/backend/src/db/migrations/061_work_order_admin_note.sql
new file mode 100644
index 00000000..554a1a54
--- /dev/null
+++ b/apps/backend/src/db/migrations/061_work_order_admin_note.sql
@@ -0,0 +1,5 @@
+-- 061_work_order_admin_note.sql —— 后台客服工单备注。
+ALTER TABLE work_orders
+  ADD COLUMN IF NOT EXISTS admin_note TEXT NOT NULL DEFAULT '';
+
+COMMENT ON COLUMN work_orders.admin_note IS '后台客服维护的工单备注，不展示给打手';
diff --git a/apps/backend/src/repositories/worker-platform/types.ts b/apps/backend/src/repositories/worker-platform/types.ts
index b3c5d38c..b6f38d46 100644
--- a/apps/backend/src/repositories/worker-platform/types.ts
+++ b/apps/backend/src/repositories/worker-platform/types.ts
@@ -355,6 +355,7 @@ export type WorkOrderRow = {
   requirement_json: string | Record<string, unknown>
   acceptance_json: string | Record<string, unknown>
   draft_acceptance_json: string | Record<string, unknown>
+  admin_note: string
   problem_note: string
   sharing_enabled: boolean
   sharing_total_quantity: number
diff --git a/apps/backend/src/repositories/worker-platform/work-order-management-repo.ts b/apps/backend/src/repositories/worker-platform/work-order-management-repo.ts
index 98043718..0e98f11a 100644
--- a/apps/backend/src/repositories/worker-platform/work-order-management-repo.ts
+++ b/apps/backend/src/repositories/worker-platform/work-order-management-repo.ts
@@ -167,6 +167,19 @@ export async function updateWorkOrderBasic(
   return getWorkOrderById(workOrderId)
 }
 
+export async function updateWorkOrderAdminNote(
+  workOrderId: number | string,
+  note: string,
+  updatedAt: string,
+): Promise<WorkOrderRow | null> {
+  const result = await query<{ id: number }>(
+    `UPDATE work_orders SET admin_note = $1, updated_at = $2 WHERE id = $3 RETURNING id`,
+    [String(note || '').trim(), updatedAt, Number(workOrderId)],
+  )
+  if (!result.rows[0]) return null
+  return getWorkOrderById(result.rows[0].id)
+}
+
 export async function deleteWorkOrder(workOrderId: number | string): Promise<boolean> {
   const result = await query('DELETE FROM work_orders WHERE id = $1', [Number(workOrderId)])
   return Number(result.rowCount || 0) > 0
diff --git a/apps/backend/src/routes/admin/worker-platform/orders.ts b/apps/backend/src/routes/admin/worker-platform/orders.ts
index 83c4de8d..ceffbbd6 100644
--- a/apps/backend/src/routes/admin/worker-platform/orders.ts
+++ b/apps/backend/src/routes/admin/worker-platform/orders.ts
@@ -23,6 +23,7 @@ import {
   unassignAdminWorkOrder,
   unpublishAdminWorkOrder,
   updateAdminWorkOrder,
+  updateAdminWorkOrderNote,
   updateAdminWorkOrderSharing,
 } from '../../../services/worker-platform/index.js'
 import {
@@ -188,6 +189,30 @@ router.put(
   ),
 )
 
+router.put(
+  '/worker-platform/orders/:workOrderId/note',
+  requireAdminPermission('worker_order.edit'),
+  createJsonHandler(
+    (req) =>
+      updateAdminWorkOrderNote(
+        String(req.params.workOrderId || ''),
+        req.body?.note,
+        req.adminSession?.username || '',
+      ),
+    {
+      successMessage: '工单备注已保存',
+      errorMessage: '保存工单备注失败',
+      scope: '[admin/worker-platform/orders/:workOrderId/note]',
+      audit: (req, data) => ({
+        action: 'work_order_admin_note_updated',
+        targetType: 'work_order',
+        targetId: String(req.params.workOrderId || ''),
+        data: data && typeof data === 'object' ? (data as Record<string, unknown>) : {},
+      }),
+    },
+  ),
+)
+
 router.post(
   '/worker-platform/orders/:workOrderId/assign',
   requireAdminPermission('worker_order.assign'),
diff --git a/apps/backend/src/services/worker-platform/admin-work-order-management-service.ts b/apps/backend/src/services/worker-platform/admin-work-order-management-service.ts
index 54a0b4ad..bd47017d 100644
--- a/apps/backend/src/services/worker-platform/admin-work-order-management-service.ts
+++ b/apps/backend/src/services/worker-platform/admin-work-order-management-service.ts
@@ -8,6 +8,7 @@ import {
   resolveProblemWorkOrder,
   updateWorkOrder,
   updateWorkOrderBasic,
+  updateWorkOrderAdminNote,
 } from '../../repositories/worker-platform/index.js'
 import type { JsonObject } from '../../types/json.js'
 import { createHttpError } from '../../utils/http.js'
@@ -111,6 +112,40 @@ export async function updateAdminWorkOrder(
   return { order: mapWorkOrderAdmin(updated || workOrder) }
 }
 
+export async function updateAdminWorkOrderNote(
+  workOrderId: number | string,
+  note: unknown,
+  actorName = '',
+) {
+  const workOrder = await getRequiredWorkOrder(workOrderId)
+  const normalizedNote = String(note ?? '').trim()
+  if (normalizedNote.length > 2000) {
+    throw createHttpError('备注不能超过 2000 个字符', {
+      statusCode: 400,
+      errorCode: 'work_order_admin_note_too_long',
+    })
+  }
+  const now = nowIso()
+  const updated = await updateWorkOrderAdminNote(workOrder.id, normalizedNote, now)
+  if (!updated) {
+    throw createHttpError('保存工单备注失败', {
+      statusCode: 409,
+      errorCode: 'work_order_admin_note_update_failed',
+    })
+  }
+  await createWorkOrderEvent({
+    workOrderId: workOrder.id,
+    actorType: 'admin',
+    actorId: actorName,
+    eventType: 'admin_note_updated',
+    fromStatus: workOrder.status,
+    toStatus: workOrder.status,
+    payloadJson: JSON.stringify({ note: normalizedNote }),
+    now,
+  })
+  return { order: mapWorkOrderAdmin(updated) }
+}
+
 export async function deleteAdminWorkOrder(workOrderId: number | string) {
   const workOrder = await getRequiredWorkOrder(workOrderId)
   if (!mapWorkOrderAdmin(workOrder).capabilities.canDelete) {
diff --git a/apps/backend/src/services/worker-platform/work-order-display-mappers.ts b/apps/backend/src/services/worker-platform/work-order-display-mappers.ts
index f28bf473..0818d4c0 100644
--- a/apps/backend/src/services/worker-platform/work-order-display-mappers.ts
+++ b/apps/backend/src/services/worker-platform/work-order-display-mappers.ts
@@ -240,6 +240,7 @@ export function mapWorkOrderAdmin(workOrder: WorkOrderRow, shares?: WorkOrderSha
     },
     acceptance: mapAcceptanceForResponse(workOrder.acceptance_json),
     draftAcceptance: mapAcceptanceForResponse(workOrder.draft_acceptance_json),
+    adminNote: workOrder.admin_note || '',
     problemNote: workOrder.problem_note || '',
     cancel:
       workOrder.status === WORK_ORDER_STATUS.CANCELLED
@@ -286,6 +287,7 @@ export function mapWorkOrderForWorker(
     rawStatus: _rawStatus,
     hallAvailable: _hallAvailable,
     capabilities: _capabilities,
+    adminNote: _adminNote,
     ...visibleOrder
   } = mapped
   const personalStatus = resolveWorkerShareStatus(workOrder.status, myShare?.status)
diff --git a/apps/frontend/src/pages/admin/panels/WorkOrdersPanel.tsx b/apps/frontend/src/pages/admin/panels/WorkOrdersPanel.tsx
index 6b0fe824..c8639622 100644
--- a/apps/frontend/src/pages/admin/panels/WorkOrdersPanel.tsx
+++ b/apps/frontend/src/pages/admin/panels/WorkOrdersPanel.tsx
@@ -67,6 +67,7 @@ import {
   submitAdminWorkOrderMaterial,
   unpublishAdminWorkOrder,
   updateAdminWorkOrder,
+  updateAdminWorkOrderNote,
   updateAdminWorkOrderSharing,
 } from '@/services/admin'
 import type { UploadedFile, WorkOrder, WorkOrderShare } from '@/types/worker-platform'
@@ -223,6 +224,7 @@ export default function WorkOrdersPanel() {
   const [assignOrder, setAssignOrder] = useState<WorkOrder | null>(null)
   const [assignWorkerId, setAssignWorkerId] = useState<number | undefined>(undefined)
   const [editOrder, setEditOrder] = useState<WorkOrder | null>(null)
+  const [noteOrder, setNoteOrder] = useState<WorkOrder | null>(null)
   const [deductOrder, setDeductOrder] = useState<WorkOrder | null>(null)
   const [cancelOrder, setCancelOrder] = useState<WorkOrder | null>(null)
   const [problemForm] = Form.useForm()
@@ -241,6 +243,7 @@ export default function WorkOrdersPanel() {
     timeoutMinutes?: number
     timeoutPolicy?: string
   }>()
+  const [noteForm] = Form.useForm<{ note?: string }>()
   const [sharingForm] = Form.useForm<{
     enabled?: boolean
     totalQuantity?: number
@@ -710,6 +713,25 @@ export default function WorkOrdersPanel() {
     })
   }
 
+  function openNoteModal(row: WorkOrder) {
+    setNoteOrder(row)
+    noteForm.setFieldsValue({ note: row.adminNote || '' })
+  }
+
+  async function submitNote(values: { note?: string }) {
+    if (!noteOrder) return
+    const succeeded = await runAction(
+      () => updateAdminWorkOrderNote(noteOrder.workOrderId, String(values.note || '')),
+      '工单备注已保存',
+    )
+    if (!succeeded) return
+    if (detailOrder?.workOrderId === noteOrder.workOrderId) {
+      setDetailOrder({ ...detailOrder, adminNote: String(values.note || '').trim() })
+    }
+    setNoteOrder(null)
+    noteForm.resetFields()
+  }
+
   function openDeductModal(row: WorkOrder) {
     setDeductOrder(row)
     deductForm.setFieldsValue({
@@ -974,6 +996,15 @@ export default function WorkOrdersPanel() {
                 {cancelText}
               </Typography.Text>
             ) : null}
+            {String(row.adminNote || '').trim() ? (
+              <Typography.Text
+                type="secondary"
+                style={{ fontSize: 12, maxWidth: 140 }}
+                ellipsis={{ tooltip: row.adminNote }}
+              >
+                备注：{row.adminNote}
+              </Typography.Text>
+            ) : null}
           </div>
         )
       },
@@ -1027,6 +1058,11 @@ export default function WorkOrdersPanel() {
       render: (_, row) => (
         <Space wrap>
           <Button onClick={() => openDetailDrawer(row)}>详情</Button>
+          {canEditOrder ? (
+            <Button icon={<FormOutlined />} onClick={() => openNoteModal(row)}>
+              备注
+            </Button>
+          ) : null}
           {row.capabilities?.canEdit && canEditOrder ? (
             <Button icon={<EditOutlined />} onClick={() => openEditModal(row)}>
               编辑
@@ -1502,6 +1538,22 @@ export default function WorkOrdersPanel() {
                     {String(detailOrder.problemNote || '').trim() || '-'}
                   </span>
                 </Descriptions.Item>
+                <Descriptions.Item label="客服备注" span={2}>
+                  <Space align="start">
+                    <span className="worker-order-detail-value">
+                      {String(detailOrder.adminNote || '').trim() || '-'}
+                    </span>
+                    {canEditOrder ? (
+                      <Button
+                        size="small"
+                        icon={<EditOutlined />}
+                        onClick={() => openNoteModal(detailOrder)}
+                      >
+                        编辑
+                      </Button>
+                    ) : null}
+                  </Space>
+                </Descriptions.Item>
                 {detailOrder.cancel ? (
                   <Descriptions.Item label="取消信息" span={2}>
                     <span className="worker-order-detail-value">
@@ -1683,6 +1735,34 @@ export default function WorkOrdersPanel() {
           </div>
         ) : null}
       </Drawer>
+      <Modal
+        title={`客服备注 · ${getDisplayOrderNo(noteOrder)}`}
+        open={Boolean(noteOrder)}
+        onCancel={() => {
+          setNoteOrder(null)
+          noteForm.resetFields()
+        }}
+        onOk={() => noteForm.submit()}
+        destroyOnHidden
+      >
+        {noteOrder ? (
+          <Form form={noteForm} layout="vertical" onFinish={submitNote}>
+            <Form.Item
+              label="备注内容"
+              name="note"
+              rules={[{ max: 2000, message: '备注不能超过 2000 个字符' }]}
+              extra="仅后台客服可见，不会展示给打手。"
+            >
+              <Input.TextArea
+                rows={5}
+                maxLength={2000}
+                showCount
+                placeholder="请输入本单客服备注"
+              />
+            </Form.Item>
+          </Form>
+        ) : null}
+      </Modal>
       <Modal
         title={`编辑工单 · ${getDisplayOrderNo(editOrder)}`}
         open={Boolean(editOrder)}
diff --git a/apps/frontend/src/services/admin/worker-platform.ts b/apps/frontend/src/services/admin/worker-platform.ts
index 9bba936b..30523ba2 100644
--- a/apps/frontend/src/services/admin/worker-platform.ts
+++ b/apps/frontend/src/services/admin/worker-platform.ts
@@ -628,6 +628,12 @@ export function updateAdminWorkOrder(
   )
 }
 
+export function updateAdminWorkOrderNote(workOrderId: number, note: string) {
+  return apiPut<{ order: WorkOrder }>(`/api/v1/admin/worker-platform/orders/${workOrderId}/note`, {
+    note,
+  })
+}
+
 export function deleteAdminWorkOrder(workOrderId: number) {
   return apiDelete<{ deleted: boolean }>(`/api/v1/admin/worker-platform/orders/${workOrderId}`)
 }
diff --git a/apps/frontend/src/types/worker-platform.ts b/apps/frontend/src/types/worker-platform.ts
index 0d8d6f46..2e3ba93d 100644
--- a/apps/frontend/src/types/worker-platform.ts
+++ b/apps/frontend/src/types/worker-platform.ts
@@ -576,6 +576,8 @@ export type WorkOrder = {
   acceptance: WorkerAcceptance
   /** 暂存的验收草稿（未提交时保存于此，刷新不丢失；提交后清空） */
   draftAcceptance: WorkerAcceptance
+  /** 后台客服维护的工单备注。 */
+  adminNote?: string
   workerNote?: string
   /** 打手本人尚未点击查看或操作过该工单。 */
   isUnread?: boolean