diff --git a/app/Http/Controllers/Admin/PlatformOrderController.php b/app/Http/Controllers/Admin/PlatformOrderController.php
index 251e046..31945b1 100644
--- a/app/Http/Controllers/Admin/PlatformOrderController.php
+++ b/app/Http/Controllers/Admin/PlatformOrderController.php
@@ -122,6 +122,30 @@ class PlatformOrderController extends Controller
             'lead_id' => ['nullable', 'integer', 'exists:platform_leads,id'],
         ]);
 
+        // 治理口径：续费单必须与订阅上下文一致（站点/套餐）。
+        // 当前阶段暂不支持“跨站点/跨套餐续费”，避免误续费/串单风险；升级/降级后续再单独建设。
+        if ((string) ($data['order_type'] ?? '') === 'renewal') {
+            $subId = (int) ($data['site_subscription_id'] ?? 0);
+            $sub = $subId > 0 ? SiteSubscription::query()->find($subId) : null;
+            if (! $sub) {
+                return redirect()->back()->withErrors([
+                    'site_subscription_id' => '续费单必须绑定有效订阅。',
+                ])->withInput();
+            }
+
+            if ((int) ($data['merchant_id'] ?? 0) !== (int) ($sub->merchant_id ?? 0)) {
+                return redirect()->back()->withErrors([
+                    'merchant_id' => '续费单站点必须与订阅所属站点一致（请从订阅维度进入下单）。',
+                ])->withInput();
+            }
+
+            if ((int) ($data['plan_id'] ?? 0) !== (int) ($sub->plan_id ?? 0)) {
+                return redirect()->back()->withErrors([
+                    'plan_id' => '续费单套餐必须与订阅当前套餐一致（当前阶段暂不支持跨套餐续费）。',
+                ])->withInput();
+            }
+        }
+
         $plan = Plan::query()->findOrFail((int) $data['plan_id']);
 
         $periodMonths = $this->periodMonthsFromBillingCycle((string) $plan->billing_cycle);
diff --git a/tests/Feature/AdminPlatformOrderStoreRenewalShouldRejectMerchantMismatchTest.php b/tests/Feature/AdminPlatformOrderStoreRenewalShouldRejectMerchantMismatchTest.php
new file mode 100644
index 0000000..1245b37
--- /dev/null
+++ b/tests/Feature/AdminPlatformOrderStoreRenewalShouldRejectMerchantMismatchTest.php
@@ -0,0 +1,76 @@
+<?php
+
+namespace Tests\Feature;
+
+use App\Models\Merchant;
+use App\Models\Plan;
+use App\Models\SiteSubscription;
+use Illuminate\Foundation\Testing\RefreshDatabase;
+use Tests\TestCase;
+
+class AdminPlatformOrderStoreRenewalShouldRejectMerchantMismatchTest extends TestCase
+{
+    use RefreshDatabase;
+
+    protected function loginAsPlatformAdmin(): void
+    {
+        $this->seed();
+
+        $this->post('/admin/login', [
+            'email' => 'platform.admin@demo.local',
+            'password' => 'Platform@123456',
+        ])->assertRedirect('/admin');
+    }
+
+    public function test_store_should_reject_renewal_when_merchant_mismatch_with_subscription(): void
+    {
+        $this->loginAsPlatformAdmin();
+
+        $merchantA = Merchant::query()->firstOrFail();
+        $merchantB = Merchant::query()->create([
+            'name' => '站点B',
+            'slug' => 'merchant-b',
+            'status' => 'active',
+        ]);
+
+        $plan = Plan::query()->create([
+            'code' => 'po_store_renewal_merchant_mismatch_plan',
+            'name' => '续费下单站点不一致拒绝测试套餐',
+            'billing_cycle' => 'monthly',
+            'price' => 10,
+            'list_price' => 10,
+            'status' => 'active',
+            'sort' => 10,
+            'published_at' => now(),
+        ]);
+
+        $sub = SiteSubscription::query()->create([
+            'merchant_id' => $merchantA->id,
+            'plan_id' => $plan->id,
+            'status' => 'activated',
+            'source' => 'manual',
+            'subscription_no' => 'SUB_PO_STORE_MERCHANT_MISMATCH_0001',
+            'plan_name' => $plan->name,
+            'billing_cycle' => $plan->billing_cycle,
+            'period_months' => 1,
+            'amount' => 10,
+            'starts_at' => now()->subDay(),
+            'ends_at' => now()->addMonth(),
+            'activated_at' => now()->subDay(),
+        ]);
+
+        $res = $this->from('/admin/platform-orders/create')->post('/admin/platform-orders', [
+            'merchant_id' => $merchantB->id,
+            'plan_id' => $plan->id,
+            'site_subscription_id' => $sub->id,
+            'order_type' => 'renewal',
+            'quantity' => 1,
+            'discount_amount' => 0,
+            'payment_channel' => 'offline',
+            'remark' => 'merchant mismatch',
+        ]);
+
+        $res->assertStatus(302);
+        $res->assertSessionHasErrors('merchant_id');
+    }
+}
diff --git a/tests/Feature/AdminPlatformOrderStoreRenewalShouldRejectPlanMismatchTest.php b/tests/Feature/AdminPlatformOrderStoreRenewalShouldRejectPlanMismatchTest.php
new file mode 100644
index 0000000..26c4661
--- /dev/null
+++ b/tests/Feature/AdminPlatformOrderStoreRenewalShouldRejectPlanMismatchTest.php
@@ -0,0 +1,82 @@
+<?php
+
+namespace Tests\Feature;
+
+use App\Models\Merchant;
+use App\Models\Plan;
+use App\Models\SiteSubscription;
+use Illuminate\Foundation\Testing\RefreshDatabase;
+use Tests\TestCase;
+
+class AdminPlatformOrderStoreRenewalShouldRejectPlanMismatchTest extends TestCase
+{
+    use RefreshDatabase;
+
+    protected function loginAsPlatformAdmin(): void
+    {
+        $this->seed();
+
+        $this->post('/admin/login', [
+            'email' => 'platform.admin@demo.local',
+            'password' => 'Platform@123456',
+        ])->assertRedirect('/admin');
+    }
+
+    public function test_store_should_reject_renewal_when_plan_mismatch_with_subscription(): void
+    {
+        $this->loginAsPlatformAdmin();
+
+        $merchant = Merchant::query()->firstOrFail();
+
+        $planA = Plan::query()->create([
+            'code' => 'po_store_renewal_plan_mismatch_plan_a',
+            'name' => '续费下单套餐不一致拒绝测试套餐A',
+            'billing_cycle' => 'monthly',
+            'price' => 10,
+            'list_price' => 10,
+            'status' => 'active',
+            'sort' => 10,
+            'published_at' => now(),
+        ]);
+
+        $planB = Plan::query()->create([
+            'code' => 'po_store_renewal_plan_mismatch_plan_b',
+            'name' => '续费下单套餐不一致拒绝测试套餐B',
+            'billing_cycle' => 'monthly',
+            'price' => 20,
+            'list_price' => 20,
+            'status' => 'active',
+            'sort' => 9,
+            'published_at' => now(),
+        ]);
+
+        $sub = SiteSubscription::query()->create([
+            'merchant_id' => $merchant->id,
+            'plan_id' => $planA->id,
+            'status' => 'activated',
+            'source' => 'manual',
+            'subscription_no' => 'SUB_PO_STORE_PLAN_MISMATCH_0001',
+            'plan_name' => $planA->name,
+            'billing_cycle' => $planA->billing_cycle,
+            'period_months' => 1,
+            'amount' => 10,
+            'starts_at' => now()->subDay(),
+            'ends_at' => now()->addMonth(),
+            'activated_at' => now()->subDay(),
+        ]);
+
+        $res = $this->from('/admin/platform-orders/create')->post('/admin/platform-orders', [
+            'merchant_id' => $merchant->id,
+            'plan_id' => $planB->id,
+            'site_subscription_id' => $sub->id,
+            'order_type' => 'renewal',
+            'quantity' => 1,
+            'discount_amount' => 0,
+            'payment_channel' => 'offline',
+            'remark' => 'plan mismatch',
+        ]);
+
+        $res->assertStatus(302);
+        $res->assertSessionHasErrors('plan_id');
+    }
+}