diff --git a/backend/app/services/product_service.py b/backend/app/services/product_service.py
index a04a874..2d89719 100644
--- a/backend/app/services/product_service.py
+++ b/backend/app/services/product_service.py
@@ -522,6 +522,7 @@ async def get_all_products(
         stmt = stmt.outerjoin(ProductionOrder, Product.order_id == ProductionOrder.id).where(
             or_(
                 Product.serial_number.ilike(kw),
+                Product.external_serial.ilike(kw),   # 业务序列号（用户自定义）
                 Product.material_name.ilike(kw),
                 cast(Product.material_id, String).ilike(kw),
                 Product.spec_model.ilike(kw),
diff --git a/frontend/src/pages/admin/AdminProductsPage.tsx b/frontend/src/pages/admin/AdminProductsPage.tsx
index 8e0c0b6..3e61ed6 100644
--- a/frontend/src/pages/admin/AdminProductsPage.tsx
+++ b/frontend/src/pages/admin/AdminProductsPage.tsx
@@ -164,7 +164,7 @@ export default function AdminProductsPage() {
         <form onSubmit={handleSearch} className="flex items-center gap-2">
           <div className="relative flex-1 max-w-xl">
             <Search className="absolute left-3 top-1/2 h-4 w-4 -translate-y-1/2 text-gray-400" />
-            <input type="text" value={keyword} onChange={(e) => setKeyword(e.target.value)} placeholder="搜索产品身份证、订单号、规格型号..." className="w-full rounded-lg border border-gray-200 py-2.5 pl-9 pr-3 text-sm focus:border-blue-400 focus:outline-none focus:ring-2 focus:ring-blue-100" />
+            <input type="text" value={keyword} onChange={(e) => setKeyword(e.target.value)} placeholder="搜索产品身份证、业务序列号、订单号、名称、规格型号..." className="w-full rounded-lg border border-gray-200 py-2.5 pl-9 pr-3 text-sm focus:border-blue-400 focus:outline-none focus:ring-2 focus:ring-blue-100" />
           </div>
           <button type="submit" disabled={loading} className="flex items-center gap-1.5 rounded-lg bg-blue-600 px-5 py-2.5 text-sm font-medium text-white hover:bg-blue-700 disabled:opacity-50">
             {loading ? <Loader2 className="h-4 w-4 animate-spin" /> : <Search className="h-4 w-4" />}查询
diff --git a/frontend/src/pages/admin/AdminTasksPage.tsx b/frontend/src/pages/admin/AdminTasksPage.tsx
index 59432cb..4a68dc5 100644
--- a/frontend/src/pages/admin/AdminTasksPage.tsx
+++ b/frontend/src/pages/admin/AdminTasksPage.tsx
@@ -573,7 +573,7 @@ export default function AdminTasksPage() {
               type="text"
               value={keyword}
               onChange={(e) => setKeyword(e.target.value)}
-              placeholder="搜索产品身份证、订单号、规格型号..."
+              placeholder="搜索产品身份证、业务序列号、订单号、名称、规格型号..."
               className="w-full rounded-lg border border-gray-200 py-2.5 pl-9 pr-8 text-sm focus:border-blue-400 focus:outline-none focus:ring-2 focus:ring-blue-100"
             />
             {keyword && (