diff --git a/backend/app/api/collection_protocol.py b/backend/app/api/collection_protocol.py
index c236a87f..c952ecdb 100644
--- a/backend/app/api/collection_protocol.py
+++ b/backend/app/api/collection_protocol.py
@@ -14,6 +14,7 @@ from app.core.menu_guard import require_admin_or_super_admin
 from app.core.response import error_response, success_response
 from app.core.utils import parse_datetime
 from app.crud import collection_protocol as cp_svc
+from app.crud import collection_region as region_svc
 from app.models.models import (
     BizCollectionProtocol,
     BizProtocolPartyCustomer,
@@ -146,6 +147,15 @@ async def list_collection_protocols(
     return success_response({"list": items, "total": total, "page": page, "pageSize": pageSize, "totalPages": tp})
 
 
+@router.get("/collection-protocols/region-managers")
+async def list_protocol_region_managers(
+    user: dict = Depends(require_admin_or_super_admin),
+    db: Session = Depends(get_db),
+):
+    tenant_no = _get_tenant_no(db, user)
+    return success_response({"list": region_svc.list_active_region_leaders(db, tenant_no=tenant_no)})
+
+
 @router.get("/collection-protocols/{protocol_id}")
 async def get_collection_protocol_detail(
     protocol_id: str,
diff --git a/backend/app/crud/collection_region.py b/backend/app/crud/collection_region.py
index 54d82f1f..9cad665d 100644
--- a/backend/app/crud/collection_region.py
+++ b/backend/app/crud/collection_region.py
@@ -496,6 +496,35 @@ def list_regions_by_staff_user(
     return map_staff_region_rows_to_list([(r[0], r[1]) for r in q.all()])
 
 
+def list_active_region_leaders(db: Session, *, tenant_no: str) -> List[Dict[str, Any]]:
+    """协议表单候选：租户内有效地区负责人，按用户去重并保留负责地区。"""
+    if not tenant_no:
+        raise ValueError("租户信息缺失")
+    rows = (
+        db.query(SysUser.id, SysUser.nick_name, BizCollectionRegionStaff.region_id)
+        .join(BizCollectionRegionStaff, BizCollectionRegionStaff.user_id == SysUser.id)
+        .join(BizCollectionRegion, BizCollectionRegion.id == BizCollectionRegionStaff.region_id)
+        .filter(
+            BizCollectionRegion.tenant_no == tenant_no,
+            BizCollectionRegion.del_flag == 0,
+            BizCollectionRegionStaff.tenant_no == tenant_no,
+            BizCollectionRegionStaff.del_flag == 0,
+            BizCollectionRegionStaff.is_leader == 1,
+            SysUser.tenant_no == tenant_no,
+            SysUser.del_flag == 0,
+            SysUser.status == "1",
+        )
+        .distinct()
+        .order_by(SysUser.nick_name.asc(), SysUser.id.asc(), BizCollectionRegionStaff.region_id.asc())
+        .all()
+    )
+    leaders: Dict[str, Dict[str, Any]] = {}
+    for user_id, nick_name, region_id in rows:
+        item = leaders.setdefault(user_id, {"id": user_id, "nickName": nick_name or "", "regionIds": []})
+        item["regionIds"].append(region_id)
+    return list(leaders.values())
+
+
 def list_staff(
     db: Session,
     *,
diff --git a/backend/tests/test_market_support_api.py b/backend/tests/test_market_support_api.py
index a3f8968e..056338c7 100644
--- a/backend/tests/test_market_support_api.py
+++ b/backend/tests/test_market_support_api.py
@@ -163,6 +163,11 @@ def test_protocol_manager_options_only_include_active_tenant_region_leaders(regi
         {'value': 'leader-c', 'label': 'c负责人'},
         {'value': 'leader-d', 'label': 'd负责人'},
     ]
+    from app.crud import collection_region
+    leaders = collection_region.list_active_region_leaders(db, tenant_no='tenant-a')
+    assert [{'value': row['id'], 'label': row['nickName']} for row in leaders] == out['regionManagers']
+    assert leaders[0]['regionIds'] == ['ra', 'rb']
+    assert all(set(row) == {'id', 'nickName', 'regionIds'} for row in leaders)
     if region_id == 'ra':
         assert 'staff-a' in {row['value'] for row in out['staff']}
         assert 'user-b' not in {row['value'] for row in out['staff']}
@@ -2518,3 +2523,25 @@ def test_payment_transfer_response_carries_server_authorized_capabilities():
         'submit-finance',
     ]
     assert pending['allowedActions'] == ['withdraw-transfer']
+
+
+def test_web_protocol_manager_options_derive_tenant_from_authenticated_user():
+    from app.api import collection_protocol
+    from app.core.menu_guard import require_admin_or_super_admin
+    db = _session()
+    _seed_options(db)
+    response = asyncio.run(collection_protocol.list_protocol_region_managers(
+        user={**_user(), 'tenant_no': 'tenant-b'}, db=db))
+    assert response['data']['list'] == [
+        {'id': 'leader-a', 'nickName': 'A负责人', 'regionIds': ['ra']},
+        {'id': 'user-b', 'nickName': 'B经理', 'regionIds': ['rb']},
+    ]
+    route = next(route for route in collection_protocol.router.routes
+                 if route.path == '/web/admin/collection-protocols/region-managers')
+    assert any(dep.call == require_admin_or_super_admin for dep in route.dependant.dependencies)
+    paths = [route.path for route in collection_protocol.router.routes]
+    assert paths.index(route.path) < paths.index('/web/admin/collection-protocols/{protocol_id}')
+    db.query(BizCollectionRegionStaff).update({'is_leader': 0})
+    db.commit()
+    assert asyncio.run(collection_protocol.list_protocol_region_managers(user=_user(), db=db))['data']['list'] == []
+    db.close()
diff --git a/web-admin/src/api/collection-protocol.ts b/web-admin/src/api/collection-protocol.ts
index 4c552057..dd610800 100644
--- a/web-admin/src/api/collection-protocol.ts
+++ b/web-admin/src/api/collection-protocol.ts
@@ -27,6 +27,14 @@ export function fetchCollectionProtocolList(params?: {
   })
 }
 
+export type ProtocolRegionManager = { id: string; nickName: string; regionIds: string[] }
+
+export function fetchProtocolRegionManagers() {
+  return request.get<{ list: ProtocolRegionManager[] }>({
+    url: '/web/admin/collection-protocols/region-managers'
+  })
+}
+
 export function fetchCollectionProtocolDetail(id: string) {
   return request.get<{
     protocol: Record<string, unknown>
diff --git a/web-admin/src/utils/protocol-region-managers.test.ts b/web-admin/src/utils/protocol-region-managers.test.ts
new file mode 100644
index 00000000..62f29371
--- /dev/null
+++ b/web-admin/src/utils/protocol-region-managers.test.ts
@@ -0,0 +1,166 @@
+import assert from 'node:assert/strict'
+import { readFileSync } from 'node:fs'
+import test from 'node:test'
+import ts from 'typescript'
+
+const source = readFileSync(
+  new URL('../views/cell-storage/protocol/ProtocolFormDialog.vue', import.meta.url),
+  'utf8'
+)
+function method(name: string) {
+  const asyncStart = source.indexOf(`  async function ${name}(`)
+  const start = asyncStart >= 0 ? asyncStart : source.indexOf(`  function ${name}(`)
+  const end = source.indexOf('\n  }', start) + 4
+  return source.slice(start, end)
+}
+function harness() {
+  const requests: Array<{ resolve: (value: any) => void; reject: (error: Error) => void }> = []
+  const hospitals: Array<{ resolve: () => void }> = []
+  const refs = {
+    managerLoading: { value: false },
+    managerUserOptions: { value: [] as any[] },
+    managerSnapshot: { value: null as any },
+    regionManagerUserId: { value: null as string | null },
+    formData: { regionId: 'a', regionManagerUserId: '' }
+  }
+  const deps = {
+    ...refs,
+    linkedRegionMode: { value: false },
+    regionOptions: { value: [] },
+    hospitalOptions: { value: [] },
+    fetchRegionsByStaffUser: async () => ({ list: [{ id: 'b', regionName: 'B区' }] }),
+    loadHospitalsByRegion: () => new Promise<void>((resolve) => hospitals.push({ resolve })),
+    fetchProtocolRegionManagers: () =>
+      new Promise((resolve, reject) => requests.push({ resolve, reject })),
+    fetchUserList: async () => ({ list: [{ id: 'member', nickName: '普通员工' }] }),
+    fetchRegionStaffList: async () => ({
+      list: [{ userId: 'member', nickName: '普通员工', isLeader: false }]
+    }),
+    makeManagerUserStub: (id: string, nickName: string) => ({ id, nickName }),
+    ElMessage: { error: () => {} }
+  }
+  const code = ts.transpileModule(
+    `let managerSearchVersion = 0; let managerDefaultVersion = 0;
+    ${method('remoteSearchManagerUsers')}
+    ${method('applyDefaultRegionManager')}
+    ${method('onManagerUserChange')}
+    ${method('applyRegionsForSalesUser')}
+    return { search: remoteSearchManagerUsers, apply: applyDefaultRegionManager, select: onManagerUserChange, applySales: applyRegionsForSalesUser }`,
+    { compilerOptions: { target: ts.ScriptTarget.ES2022 } }
+  ).outputText
+  return {
+    ...refs,
+    requests,
+    hospitals,
+    ...new Function(...Object.keys(deps), code)(...Object.values(deps))
+  }
+}
+const leaders = [
+  { id: 'head-a', nickName: 'A负责人', regionIds: ['a'] },
+  { id: 'head-b', nickName: 'B负责人', regionIds: ['b'] }
+]
+
+test('manager search uses all region leaders without appending historical ordinary users', async () => {
+  const h = harness()
+  h.regionManagerUserId.value = 'member'
+  h.managerSnapshot.value = { id: 'member', nickName: '历史人员' }
+  const pending = h.search('')
+  h.requests[0]?.resolve({ list: leaders })
+  await pending
+  assert.deepEqual(
+    h.managerUserOptions.value.map((u: any) => u.id),
+    ['head-a', 'head-b']
+  )
+  assert.equal(h.managerSnapshot.value.nickName, '历史人员')
+})
+
+test('a region without a leader stays empty instead of defaulting to an ordinary member', async () => {
+  const h = harness()
+  const pending = h.apply('a')
+  h.requests[0]?.resolve({ list: [leaders[1]] })
+  await pending
+  assert.equal(h.formData.regionManagerUserId, '')
+  assert.equal(h.regionManagerUserId.value, null)
+})
+
+test('default manager belongs to selected region while candidates include all leaders', async () => {
+  const h = harness()
+  const pending = h.apply('a')
+  h.requests[0]?.resolve({ list: leaders })
+  await pending
+  assert.equal(h.formData.regionManagerUserId, 'head-a')
+  assert.deepEqual(
+    h.managerUserOptions.value.map((u: any) => u.id),
+    ['head-a', 'head-b']
+  )
+})
+
+test('clearing a region invalidates pending manager defaults', async () => {
+  const h = harness()
+  const pending = h.apply('a')
+  h.formData.regionId = ''
+  await h.apply('')
+  h.requests[0]?.resolve({ list: leaders })
+  await pending
+  assert.equal(h.formData.regionManagerUserId, '')
+})
+
+test('out-of-order manager searches cannot overwrite the latest result', async () => {
+  const h = harness()
+  const first = h.search('A')
+  const second = h.search('B')
+  h.requests[1]?.resolve({ list: leaders })
+  await second
+  h.requests[0]?.resolve({ list: leaders })
+  await first
+  assert.deepEqual(
+    h.managerUserOptions.value.map((u: any) => u.id),
+    ['head-b']
+  )
+})
+
+test('a manual selection is not overwritten by a pending default response', async () => {
+  const h = harness()
+  const pending = h.apply('a')
+  h.managerUserOptions.value = leaders
+  h.select('head-b')
+  h.requests[0].resolve({ list: leaders })
+  await pending
+  assert.equal(h.formData.regionManagerUserId, 'head-b')
+})
+
+test('failed manager loading clears the old default and never falls back to ordinary users', async () => {
+  const h = harness()
+  h.formData.regionManagerUserId = 'old'
+  h.regionManagerUserId.value = 'old'
+  const pending = h.apply('a')
+  h.requests[0].reject(new Error('network failure'))
+  await pending
+  assert.equal(h.formData.regionManagerUserId, '')
+  assert.deepEqual(h.managerUserOptions.value, [])
+})
+
+test('a delayed default call for an old region cannot clear the current manager', async () => {
+  const h = harness()
+  h.formData.regionId = 'b'
+  h.formData.regionManagerUserId = 'head-b'
+  h.regionManagerUserId.value = 'head-b'
+  const pending = h.apply('a')
+  h.requests[0]?.resolve({ list: leaders })
+  await pending
+  assert.equal(h.formData.regionManagerUserId, 'head-b')
+  assert.equal(h.regionManagerUserId.value, 'head-b')
+})
+
+test('sales-linked region loading does not overwrite a manager chosen while hospitals load', async () => {
+  const h = harness()
+  const pending = h.applySales('sales-b')
+  await Promise.resolve()
+  h.managerUserOptions.value = leaders
+  h.select('head-a')
+  h.hospitals[0].resolve()
+  await Promise.resolve()
+  h.requests[0].resolve({ list: leaders })
+  await pending
+  assert.equal(h.formData.regionManagerUserId, 'head-a')
+})
diff --git a/web-admin/src/views/cell-storage/protocol/ProtocolFormDialog.vue b/web-admin/src/views/cell-storage/protocol/ProtocolFormDialog.vue
index 82ea62ec..625ee90d 100644
--- a/web-admin/src/views/cell-storage/protocol/ProtocolFormDialog.vue
+++ b/web-admin/src/views/cell-storage/protocol/ProtocolFormDialog.vue
@@ -154,10 +154,21 @@
                   clearable
                   reserve-keyword
                   :remote-method="remoteSearchManagerUsers"
+                  @visible-change="(visible: boolean) => visible && remoteSearchManagerUsers('')"
                   :loading="managerLoading"
                   placeholder="默认取地区负责人，可修改"
                   @change="onManagerUserChange"
                 >
+                  <el-option
+                    v-if="
+                      managerSnapshot &&
+                      !managerUserOptions.some((u) => u.id === managerSnapshot?.id)
+                    "
+                    v-show="false"
+                    :label="managerSnapshot.nickName"
+                    :value="managerSnapshot.id"
+                    disabled
+                  />
                   <el-option
                     v-for="u in managerUserOptions"
                     :key="u.id"
@@ -1162,6 +1173,7 @@
   } from '@element-plus/icons-vue'
   import {
     fetchCollectionProtocolDetail,
+    fetchProtocolRegionManagers,
     fetchCreateCollectionProtocol,
     fetchUpdateCollectionProtocol,
     fetchSubmitReceiptFinance,
@@ -1188,7 +1200,6 @@
     fetchItemUnitList,
     fetchCollectionRegionList,
     fetchHospitalList,
-    fetchRegionStaffList,
     fetchRegionsByStaffUser,
     fetchSampleCodeList,
     fetchExpressCompanyList,
@@ -1308,7 +1319,9 @@
   const salesSnapshot = ref<Api.User.UserItem | null>(null)
 
   const regionManagerUserId = ref<string | null>(null)
-  const managerUserOptions = ref<Api.User.UserItem[]>([])
+  const managerUserOptions = ref<Array<Api.User.UserItem & { regionIds: string[] }>>([])
+  let managerSearchVersion = 0
+  let managerDefaultVersion = 0
   const managerLoading = ref(false)
   const managerSnapshot = ref<Api.User.UserItem | null>(null)
   const linkedRegionMode = ref(false)
@@ -1607,6 +1620,9 @@
   }
 
   function resetForm() {
+    managerSearchVersion++
+    managerDefaultVersion++
+    managerLoading.value = false
     Object.assign(formData, {
       protocolNo: '',
       protocolNoId: '',
@@ -2729,7 +2745,6 @@
       (user) => {
         managerSnapshot.value = { ...user }
         regionManagerUserId.value = user.id
-        managerUserOptions.value = [{ ...user }]
         formData.regionManagerUserId = user.id
       },
       () => {
@@ -2739,6 +2754,7 @@
         formData.regionManagerUserId = ''
       }
     )
+    await remoteSearchManagerUsers('')
   }
 
   function makeManagerUserStub(id: string, name: string): Api.User.UserItem {
@@ -2974,28 +2990,29 @@
   }
 
   async function remoteSearchManagerUsers(query: string) {
+    const version = ++managerSearchVersion
     managerLoading.value = true
     try {
-      const res = await fetchUserList({
-        page: 1,
-        pageSize: 50,
-        keyword: (query || '').trim() || undefined,
-        status: '1'
-      })
-      let list = [...(res.list || [])]
-      const cur = regionManagerUserId.value
-      if (cur && !list.some((x) => x.id === cur)) {
-        const keep =
-          managerSnapshot.value?.id === cur
-            ? managerSnapshot.value
-            : managerUserOptions.value.find((x) => x.id === cur)
-        if (keep) list = [keep, ...list]
+      const res = await fetchProtocolRegionManagers()
+      const keyword = (query || '').trim().toLowerCase()
+      const list = (res.list || []).map((item) => ({
+        ...makeManagerUserStub(item.id, item.nickName),
+        regionIds: item.regionIds
+      }))
+      if (version === managerSearchVersion) {
+        managerUserOptions.value = list.filter((item) =>
+          item.nickName.toLowerCase().includes(keyword)
+        )
       }
-      managerUserOptions.value = list
+      return list
     } catch {
-      managerUserOptions.value = []
+      if (version === managerSearchVersion) {
+        managerUserOptions.value = []
+        ElMessage.error('地区负责人加载失败，请重试')
+      }
+      return []
     } finally {
-      managerLoading.value = false
+      if (version === managerSearchVersion) managerLoading.value = false
     }
   }
 
@@ -3016,53 +3033,34 @@
   }
 
   function onManagerUserChange(val: string | null | undefined) {
+    managerDefaultVersion++
     if (!val) {
       regionManagerUserId.value = null
       managerSnapshot.value = null
       formData.regionManagerUserId = ''
       return
     }
-    const u = managerUserOptions.value.find((x) => x.id === val) || managerSnapshot.value
-    if (!u) {
-      regionManagerUserId.value = val
-      formData.regionManagerUserId = val
-      return
-    }
+    const u = managerUserOptions.value.find((x) => x.id === val)
+    if (!u) return
     managerSnapshot.value = { ...u }
     regionManagerUserId.value = u.id
     formData.regionManagerUserId = u.id
   }
 
   async function applyDefaultRegionManager(regionId: string) {
-    if (!regionId) {
-      regionManagerUserId.value = null
-      formData.regionManagerUserId = ''
-      managerUserOptions.value = []
-      managerSnapshot.value = null
-      return
-    }
-    try {
-      const res: any = await fetchRegionStaffList(regionId, { page: 1, pageSize: 100 })
-      const list = (res?.list || []) as Array<Record<string, any>>
-      const leader = list.find((x) => x.isLeader) || list[0]
-      if (!leader?.userId) {
-        regionManagerUserId.value = null
-        formData.regionManagerUserId = ''
-        return
-      }
-      const stub = makeManagerUserStub(
-        String(leader.userId),
-        String(leader.nickName || leader.userName || '')
-      )
-      regionManagerUserId.value = stub.id
-      formData.regionManagerUserId = stub.id
-      managerSnapshot.value = { ...stub }
-      if (!managerUserOptions.value.some((x) => x.id === stub.id)) {
-        managerUserOptions.value = [stub, ...managerUserOptions.value]
-      }
-    } catch {
-      /* 地区无人员配置时留空，可手工选择 */
-    }
+    if (formData.regionId !== regionId) return
+    const version = ++managerDefaultVersion
+    regionManagerUserId.value = null
+    formData.regionManagerUserId = ''
+    managerSnapshot.value = null
+    if (!regionId) return
+    const list = await remoteSearchManagerUsers('')
+    if (version !== managerDefaultVersion || formData.regionId !== regionId) return
+    const leader = list.find((item) => item.regionIds.includes(regionId))
+    if (!leader) return
+    regionManagerUserId.value = leader.id
+    formData.regionManagerUserId = leader.id
+    managerSnapshot.value = { ...leader }
   }
 
   async function applyRegionsForSalesUser(
@@ -3112,10 +3110,10 @@
         if (regionChanged) {
           formData.hospitalId = ''
           hospitalOptions.value = []
-          await loadHospitalsByRegion(nextId, '')
-          if (!opts?.skipManagerDefault) {
-            await applyDefaultRegionManager(nextId)
-          }
+          await Promise.all([
+            loadHospitalsByRegion(nextId, ''),
+            ...(opts?.skipManagerDefault ? [] : [applyDefaultRegionManager(nextId)])
+          ])
         } else if (!opts?.skipManagerDefault && !formData.regionManagerUserId) {
           await applyDefaultRegionManager(nextId)
         }
@@ -3246,6 +3244,7 @@
   }
 
   async function onRegionChange(val: string | null | undefined) {
+    managerDefaultVersion++
     if (!val) {
       formData.regionId = ''
       hospitalOptions.value = []
@@ -3259,11 +3258,11 @@
     formData.regionId = val
     formData.hospitalId = ''
     hospitalOptions.value = []
-    await loadHospitalsByRegion(val)
-    await applyDefaultRegionManager(val)
+    await Promise.all([loadHospitalsByRegion(val), applyDefaultRegionManager(val)])
   }
 
   function onRegionClear() {
+    managerDefaultVersion++
     formData.regionId = ''
     formData.hospitalId = ''
     hospitalOptions.value = []