diff --git a/app/Http/Controllers/Business/Pages.php b/app/Http/Controllers/Business/Pages.php
index 00e095b3..df0ca982 100644
--- a/app/Http/Controllers/Business/Pages.php
+++ b/app/Http/Controllers/Business/Pages.php
@@ -812,22 +812,22 @@ class Pages extends Controller
                     : '（未匹配）';
 
                 fputcsv($csv, [
-                    $this->csvText($approvalNumber),
+                    $this->csvIdentifier($approvalNumber),
                     $this->csvText($workflow['title'] ?? ''),
                     $this->csvText($row['status_label'] ?? ''),
                     $this->csvText($originator),
                     $this->csvText($row['payee_name'] ?? ''),
-                    $this->csvText($row['product_id'] ?? ''),
+                    $this->csvIdentifier($row['product_id'] ?? ''),
                     $this->csvText($productName),
                     $this->csvText($row['shop_name'] ?? ''),
-                    $this->csvText($row['daifa_trade_no'] ?? ''),
-                    $this->csvText($row['shop_trade_no'] ?? ''),
+                    $this->csvIdentifier($row['daifa_trade_no'] ?? ''),
+                    $this->csvIdentifier($row['shop_trade_no'] ?? ''),
                     $row['ship_qty'] ?? null,
                     $row['paid_amount'] ?? null,
                     $row['daifa_amount'] ?? null,
                     $row['price_diff'] ?? null,
                     $this->csvText($row['supplier_name'] ?? ''),
-                    $this->csvText($row['material_no'] ?? ''),
+                    $this->csvIdentifier($row['material_no'] ?? ''),
                     $this->csvText($row['workflow_created_at'] ?? ''),
                 ]);
             }
@@ -2076,6 +2076,22 @@ class Pages extends Controller
         return preg_match('/^[=+\-@]/u', $text) === 1 ? "'" . $text : $text;
     }
 
+    /**
+     * Export identifiers as text so Excel does not round or truncate long IDs.
+     * Keep the formula-injection guard from csvText for values beginning with a
+     * formula marker.
+     */
+    private function csvIdentifier(mixed $value): string
+    {
+        $text = $this->csvText($value);
+
+        if ($text === '' || str_starts_with($text, "'")) {
+            return $text;
+        }
+
+        return "'" . $text;
+    }
+
     private function emptyProductCatalogContent(
         array $filters,
         int $limit,
diff --git a/database/migrations/2026_09_09_130000_add_daifa_material_no_index.php b/database/migrations/2026_09_09_130000_add_daifa_material_no_index.php
new file mode 100644
index 00000000..a7ef1d83
--- /dev/null
+++ b/database/migrations/2026_09_09_130000_add_daifa_material_no_index.php
@@ -0,0 +1,51 @@
+<?php
+
+use Illuminate\Database\Migrations\Migration;
+use Illuminate\Database\Schema\Blueprint;
+use Illuminate\Support\Facades\Schema;
+
+return new class extends Migration
+{
+    private const TABLE = 'ding_online_daifa_price_mirror';
+
+    private const INDEX = 'idx_daifa_material_no';
+
+    private function connection(): string
+    {
+        return (string) config('upstream_mirrors.connection', 'business_mirror');
+    }
+
+    public function up(): void
+    {
+        if (app()->environment('testing')
+            || (string) config('system_database.mode', 'bootstrap') === 'bootstrap') {
+            return;
+        }
+
+        $schema = Schema::connection($this->connection());
+        if (! $schema->hasTable(self::TABLE) || $schema->hasIndex(self::TABLE, self::INDEX)) {
+            return;
+        }
+
+        $schema->table(self::TABLE, function (Blueprint $table): void {
+            $table->index('material_no', self::INDEX);
+        });
+    }
+
+    public function down(): void
+    {
+        if (app()->environment('testing')
+            || (string) config('system_database.mode', 'bootstrap') === 'bootstrap') {
+            return;
+        }
+
+        $schema = Schema::connection($this->connection());
+        if (! $schema->hasTable(self::TABLE) || ! $schema->hasIndex(self::TABLE, self::INDEX)) {
+            return;
+        }
+
+        $schema->table(self::TABLE, function (Blueprint $table): void {
+            $table->dropIndex(self::INDEX);
+        });
+    }
+};
diff --git a/tests/Feature/Business/OnlineDaifaPricePageTest.php b/tests/Feature/Business/OnlineDaifaPricePageTest.php
index 59ffab9d..b39e821a 100644
--- a/tests/Feature/Business/OnlineDaifaPricePageTest.php
+++ b/tests/Feature/Business/OnlineDaifaPricePageTest.php
@@ -155,9 +155,9 @@ class OnlineDaifaPricePageTest extends FeatureTestCase
         $repository->shouldReceive('exportRows')->once()->with($filters)->andReturn((static function (): \Generator {
             yield [
                 'process_instance_id' => 'PROCESS-001',
-                'product_id' => 'PRODUCT-001',
-                'daifa_trade_no' => 'DAIFA-001',
-                'shop_trade_no' => 'SHOP-001',
+                'product_id' => '3821829253650055444',
+                'daifa_trade_no' => '6927049845766979458',
+                'shop_trade_no' => '6927049845766979459',
                 'shop_name' => '抖音旗舰店',
                 'payee_name' => '宁波顾家望业家居有限公司',
                 'supplier_name' => '@新北供应商',
@@ -190,6 +190,9 @@ class OnlineDaifaPricePageTest extends FeatureTestCase
         $this->assertStringContainsString("'=APPROVAL-001", $content);
         $this->assertStringContainsString("'+扬灵", $content);
         $this->assertStringContainsString("'@新北供应商", $content);
+        $this->assertStringContainsString("'3821829253650055444", $content);
+        $this->assertStringContainsString("'6927049845766979458", $content);
+        $this->assertStringContainsString("'6927049845766979459", $content);
         $this->assertStringContainsString('MAT-001', $content);
     }