diff --git a/resources/views/admin/platform_orders/show.blade.php b/resources/views/admin/platform_orders/show.blade.php
index 8bdd9f8..19b6772 100644
--- a/resources/views/admin/platform_orders/show.blade.php
+++ b/resources/views/admin/platform_orders/show.blade.php
@@ -238,10 +238,11 @@
                 <th>订阅管理</th>
                 <td>
                     @php
-                        $subBack = '/admin/platform-orders/' . $order->id;
+                        // 用 orderShowSelf 作为 back（已剔除 back query，避免嵌套膨胀）
+                        $subBack = $orderShowSelf;
                         $openSubUrl = '/admin/site-subscriptions/' . $order->siteSubscription->id . '?' . \Illuminate\Support\Arr::query(['back' => $subBack]);
                     @endphp
-                    <a class="link" href="{{ $openSubUrl }}">打开订阅详情</a>
+                    <a class="link" href="{!! $openSubUrl !!}">打开订阅详情</a>
                     <span class="muted">｜</span>
                     @php
                         $openSubSyncableUrl = '/admin/site-subscriptions/' . $order->siteSubscription->id . '?' . \Illuminate\Support\Arr::query([
@@ -249,11 +250,23 @@
                             'order_sync_status' => 'syncable',
                         ]) . '#syncable-batch';
                     @endphp
-                    <a class="muted" href="{{ $openSubSyncableUrl }}">查看可同步订单</a>
+                    <a class="muted" href="{!! $openSubSyncableUrl !!}">查看可同步订单</a>
                     <span class="muted">｜</span>
-                    <a class="muted" href="/admin/site-subscriptions?merchant_id={{ $order->siteSubscription->merchant_id }}">同站点订阅</a>
+                    @php
+                        $sameMerchantSubsUrl = '/admin/site-subscriptions?' . \Illuminate\Support\Arr::query([
+                            'merchant_id' => $order->siteSubscription->merchant_id,
+                            'back' => $orderShowSelf,
+                        ]);
+                    @endphp
+                    <a class="muted" href="{!! $sameMerchantSubsUrl !!}">同站点订阅</a>
                     <span class="muted">｜</span>
-                    <a class="muted" href="/admin/site-subscriptions?plan_id={{ $order->siteSubscription->plan_id }}">同套餐订阅</a>
+                    @php
+                        $samePlanSubsUrl = '/admin/site-subscriptions?' . \Illuminate\Support\Arr::query([
+                            'plan_id' => $order->siteSubscription->plan_id,
+                            'back' => $orderShowSelf,
+                        ]);
+                    @endphp
+                    <a class="muted" href="{!! $samePlanSubsUrl !!}">同套餐订阅</a>
                 </td>
             </tr>
             <tr><th>状态</th><td>{{ $order->siteSubscription->status }}</td></tr>
diff --git a/tests/Feature/AdminPlatformOrderShowRelatedSubscriptionLinksAreNotEscapedTest.php b/tests/Feature/AdminPlatformOrderShowRelatedSubscriptionLinksAreNotEscapedTest.php
new file mode 100644
index 0000000..6f2a836
--- /dev/null
+++ b/tests/Feature/AdminPlatformOrderShowRelatedSubscriptionLinksAreNotEscapedTest.php
@@ -0,0 +1,82 @@
+<?php
+
+namespace Tests\Feature;
+
+use App\Models\Merchant;
+use App\Models\Plan;
+use App\Models\PlatformOrder;
+use App\Models\SiteSubscription;
+use Illuminate\Foundation\Testing\RefreshDatabase;
+use Tests\TestCase;
+
+class AdminPlatformOrderShowRelatedSubscriptionLinksAreNotEscapedTest 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_related_subscription_links_should_not_render_amp_escaped_query_delimiter(): void
+    {
+        $this->loginAsPlatformAdmin();
+
+        $merchant = Merchant::query()->firstOrFail();
+        $plan = Plan::query()->create([
+            'code' => 'po_show_related_sub_no_escape_plan',
+            'name' => '平台订单详情关联订阅链接不转义测试套餐',
+            'billing_cycle' => 'monthly',
+            'price' => 10,
+            'list_price' => 10,
+            'status' => 'active',
+            'sort' => 10,
+            'published_at' => now(),
+        ]);
+
+        $sub = SiteSubscription::query()->create([
+            'merchant_id' => $merchant->id,
+            'plan_id' => $plan->id,
+            'status' => 'activated',
+            'source' => 'manual',
+            'subscription_no' => 'SUB_PO_SHOW_RELATED_NO_ESCAPE_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(),
+        ]);
+
+        $order = PlatformOrder::query()->create([
+            'merchant_id' => $merchant->id,
+            'plan_id' => $plan->id,
+            'site_subscription_id' => $sub->id,
+            'order_no' => 'PO_SHOW_RELATED_NO_ESCAPE_0001',
+            'order_type' => 'new_purchase',
+            'status' => 'pending',
+            'payment_status' => 'unpaid',
+            'plan_name' => $plan->name,
+            'billing_cycle' => $plan->billing_cycle,
+            'period_months' => 1,
+            'quantity' => 1,
+            'payable_amount' => 10,
+            'paid_amount' => 0,
+            'placed_at' => now(),
+            'meta' => [],
+        ]);
+
+        $res = $this->get('/admin/platform-orders/' . $order->id);
+        $res->assertOk();
+
+        // 关键点：openSubSyncableUrl 带两个 query 参数，不能被渲染成 &amp;
+        $res->assertDontSee('order_sync_status=syncable&amp;', false);
+        $res->assertDontSee('back=%2Fadmin%2Fplatform-orders%2F' . $order->id . '&amp;', false);
+    }
+}
diff --git a/tests/Feature/AdminPlatformOrderShowRelatedSubscriptionLinksContainBackTest.php b/tests/Feature/AdminPlatformOrderShowRelatedSubscriptionLinksContainBackTest.php
new file mode 100644
index 0000000..3bb820a
--- /dev/null
+++ b/tests/Feature/AdminPlatformOrderShowRelatedSubscriptionLinksContainBackTest.php
@@ -0,0 +1,105 @@
+<?php
+
+namespace Tests\Feature;
+
+use App\Models\Merchant;
+use App\Models\Plan;
+use App\Models\PlatformOrder;
+use App\Models\SiteSubscription;
+use Illuminate\Foundation\Testing\RefreshDatabase;
+use Illuminate\Support\Arr;
+use Tests\TestCase;
+
+class AdminPlatformOrderShowRelatedSubscriptionLinksContainBackTest 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_related_subscription_links_should_carry_back_to_platform_order_show(): void
+    {
+        $this->loginAsPlatformAdmin();
+
+        $merchant = Merchant::query()->firstOrFail();
+        $plan = Plan::query()->create([
+            'code' => 'po_show_related_sub_back_plan',
+            'name' => '平台订单详情关联订阅 back 链接测试套餐',
+            'billing_cycle' => 'monthly',
+            'price' => 10,
+            'list_price' => 10,
+            'status' => 'active',
+            'sort' => 10,
+            'published_at' => now(),
+        ]);
+
+        $sub = SiteSubscription::query()->create([
+            'merchant_id' => $merchant->id,
+            'plan_id' => $plan->id,
+            'status' => 'activated',
+            'source' => 'manual',
+            'subscription_no' => 'SUB_PO_SHOW_RELATED_BACK_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(),
+        ]);
+
+        $order = PlatformOrder::query()->create([
+            'merchant_id' => $merchant->id,
+            'plan_id' => $plan->id,
+            'site_subscription_id' => $sub->id,
+            'order_no' => 'PO_SHOW_RELATED_BACK_0001',
+            'order_type' => 'new_purchase',
+            'status' => 'pending',
+            'payment_status' => 'unpaid',
+            'plan_name' => $plan->name,
+            'billing_cycle' => $plan->billing_cycle,
+            'period_months' => 1,
+            'quantity' => 1,
+            'payable_amount' => 10,
+            'paid_amount' => 0,
+            'placed_at' => now(),
+            'meta' => [],
+        ]);
+
+        $res = $this->get('/admin/platform-orders/' . $order->id);
+        $res->assertOk();
+
+        $back = '/admin/platform-orders/' . $order->id;
+
+        $openSubUrl = '/admin/site-subscriptions/' . $sub->id . '?' . Arr::query([
+            'back' => $back,
+        ]);
+
+        $openSubSyncableUrl = '/admin/site-subscriptions/' . $sub->id . '?' . Arr::query([
+            'back' => $back,
+            'order_sync_status' => 'syncable',
+        ]) . '#syncable-batch';
+
+        $sameMerchantSubsUrl = '/admin/site-subscriptions?' . Arr::query([
+            'merchant_id' => $merchant->id,
+            'back' => $back,
+        ]);
+
+        $samePlanSubsUrl = '/admin/site-subscriptions?' . Arr::query([
+            'plan_id' => $plan->id,
+            'back' => $back,
+        ]);
+
+        $res->assertSee($openSubUrl, false);
+        $res->assertSee($openSubSyncableUrl, false);
+        $res->assertSee($sameMerchantSubsUrl, false);
+        $res->assertSee($samePlanSubsUrl, false);
+    }
+}
diff --git a/tests/Feature/AdminPlatformOrderShowRelatedSubscriptionLinksShouldNotNestBackTest.php b/tests/Feature/AdminPlatformOrderShowRelatedSubscriptionLinksShouldNotNestBackTest.php
new file mode 100644
index 0000000..670ff4b
--- /dev/null
+++ b/tests/Feature/AdminPlatformOrderShowRelatedSubscriptionLinksShouldNotNestBackTest.php
@@ -0,0 +1,82 @@
+<?php
+
+namespace Tests\Feature;
+
+use App\Models\Merchant;
+use App\Models\Plan;
+use App\Models\PlatformOrder;
+use App\Models\SiteSubscription;
+use Illuminate\Foundation\Testing\RefreshDatabase;
+use Tests\TestCase;
+
+class AdminPlatformOrderShowRelatedSubscriptionLinksShouldNotNestBackTest 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_related_subscription_links_back_should_not_contain_nested_back(): void
+    {
+        $this->loginAsPlatformAdmin();
+
+        $merchant = Merchant::query()->firstOrFail();
+        $plan = Plan::query()->create([
+            'code' => 'po_show_related_sub_no_nested_back_plan',
+            'name' => '平台订单详情关联订阅 back 不嵌套测试套餐',
+            'billing_cycle' => 'monthly',
+            'price' => 10,
+            'list_price' => 10,
+            'status' => 'active',
+            'sort' => 10,
+            'published_at' => now(),
+        ]);
+
+        $sub = SiteSubscription::query()->create([
+            'merchant_id' => $merchant->id,
+            'plan_id' => $plan->id,
+            'status' => 'activated',
+            'source' => 'manual',
+            'subscription_no' => 'SUB_PO_SHOW_NO_NEST_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(),
+        ]);
+
+        $order = PlatformOrder::query()->create([
+            'merchant_id' => $merchant->id,
+            'plan_id' => $plan->id,
+            'site_subscription_id' => $sub->id,
+            'order_no' => 'PO_SHOW_NO_NEST_0001',
+            'order_type' => 'new_purchase',
+            'status' => 'pending',
+            'payment_status' => 'unpaid',
+            'plan_name' => $plan->name,
+            'billing_cycle' => $plan->billing_cycle,
+            'period_months' => 1,
+            'quantity' => 1,
+            'payable_amount' => 10,
+            'paid_amount' => 0,
+            'placed_at' => now(),
+            'meta' => [],
+        ]);
+
+        // 带 back 访问订单详情页（模拟从列表进入）
+        $res = $this->get('/admin/platform-orders/' . $order->id . '?back=' . urlencode('/admin/platform-orders?status=pending'));
+        $res->assertOk();
+
+        // 关联订阅的 back 应该回到“订单详情（去掉 back）”，不应出现 back=...back= 的嵌套
+        $res->assertDontSee('back%3D', false);
+    }
+}