diff --git a/routes/products.py b/routes/products.py
index 3758612..135ec4c 100644
--- a/routes/products.py
+++ b/routes/products.py
@@ -265,7 +265,9 @@ def products_list():
     if supplier_filter:
         where.append("(s.supplier_name LIKE %s OR p.supplier_name_match LIKE %s)")
         params.extend([f"%{supplier_filter}%", f"%{supplier_filter}%"])
-    if brand_filter:
+    if brand_filter == '__EMPTY__':
+        where.append("(p.brand IS NULL OR TRIM(p.brand)='')")
+    elif brand_filter:
         where.append("TRIM(p.brand)=%s")
         params.append(brand_filter)
     if category1_filter:
@@ -405,10 +407,17 @@ def products_filters():
         f"SELECT DISTINCT category1 FROM products WHERE {scope_clause}"
         "category1 IS NOT NULL AND category1 != '' ORDER BY category1"
     )
+    empty_brand_count = query(
+        f"SELECT COUNT(*) AS cnt FROM products WHERE {scope_clause}"
+        "(brand IS NULL OR TRIM(brand) = '')"
+    )[0]['cnt']
+    brand_values = [b['brand'] for b in brands]
+    if empty_brand_count:
+        brand_values.insert(0, '__EMPTY__')
     return jsonify({
         "code": 0,
         "data": {
-            "brands": [b['brand'] for b in brands],
+            "brands": brand_values,
             "categories": [c['category1'] for c in categories]
         }
     })
@@ -2086,7 +2095,9 @@ def products_recycle_bin():
     if supplier_filter:
         where.append("(p.supplier_name_match LIKE %s OR s.supplier_name LIKE %s)")
         params.extend([f"%{supplier_filter}%", f"%{supplier_filter}%"])
-    if brand_filter:
+    if brand_filter == '__EMPTY__':
+        where.append("(p.brand IS NULL OR TRIM(p.brand)='')")
+    elif brand_filter:
         where.append("TRIM(p.brand)=%s")
         params.append(brand_filter)
     if product_type:
diff --git a/static/js/app.js b/static/js/app.js
index c4ead29..a901e1a 100644
--- a/static/js/app.js
+++ b/static/js/app.js
@@ -8322,7 +8322,8 @@ function loadProductBrandFilter(tab) {
             if (!document.body.contains(sel) || !res || res.code !== 0) return;
             var brands = (res.data && res.data.brands) || [];
             sel.innerHTML = '<option value="">全部品牌</option>' + brands.map(function(brand) {
-                return '<option value="' + escHtml(brand) + '">' + escHtml(brand) + '</option>';
+                var label = brand === '__EMPTY__' ? '（品牌为空）' : brand;
+                return '<option value="' + escHtml(brand) + '">' + escHtml(label) + '</option>';
             }).join('');
         });
 }
diff --git a/tests/test_product_brand_filter.py b/tests/test_product_brand_filter.py
index 6ba47a0..894c11b 100644
--- a/tests/test_product_brand_filter.py
+++ b/tests/test_product_brand_filter.py
@@ -18,6 +18,7 @@ class ProductBrandFilterStaticTest(unittest.TestCase):
         self.assertIn("loadProductBrandFilter('成品')", APP_JS)
         self.assertIn('loadProductBrandFilter(tab)', APP_JS)
         self.assertGreaterEqual(APP_JS.count("url += '&brand='"), 2)
+        self.assertIn("brand === '__EMPTY__' ? '（品牌为空）' : brand", APP_JS)
 
 
 class ProductBrandFilterApiTest(unittest.TestCase):
@@ -35,16 +36,43 @@ class ProductBrandFilterApiTest(unittest.TestCase):
         self.assertIn('TRIM(p.brand)=%s', query.call_args_list[0].args[0])
         self.assertEqual(query.call_args_list[0].args[1], ['无'])
 
+    def test_active_products_filter_empty_brand(self):
+        with mock.patch.object(products, 'query', side_effect=[[], [{'cnt': 0}], []]) as query:
+            response = self.client.get('/api/products/list?brand=__EMPTY__')
+
+        self.assertEqual(response.get_json()['code'], 0)
+        self.assertIn("(p.brand IS NULL OR TRIM(p.brand)='')", query.call_args_list[1].args[0])
+        self.assertEqual(query.call_args_list[1].args[1], [])
+
+    def test_recycle_bin_filters_empty_brand(self):
+        with mock.patch.object(products, 'query', side_effect=[[{'cnt': 0}], []]) as query:
+            response = self.client.get('/api/products/recycle_bin?brand=__EMPTY__')
+
+        self.assertEqual(response.get_json()['code'], 0)
+        self.assertIn("(p.brand IS NULL OR TRIM(p.brand)='')", query.call_args_list[0].args[0])
+        self.assertEqual(query.call_args_list[0].args[1], [])
+
     def test_filter_options_can_be_scoped_to_recycle_bin(self):
         with mock.patch.object(products, 'query', side_effect=[
                 [{'brand': '回收品牌'}],
                 [{'category1': '分类'}],
+                [{'cnt': 2}],
         ]) as query:
             response = self.client.get('/api/products/filters?scope=recycle')
 
-        self.assertEqual(response.get_json()['data']['brands'], ['回收品牌'])
+        self.assertEqual(response.get_json()['data']['brands'], ['__EMPTY__', '回收品牌'])
         self.assertIn('deleted_at IS NOT NULL', query.call_args_list[0].args[0])
 
+    def test_filter_options_omit_empty_brand_when_scope_has_none(self):
+        with mock.patch.object(products, 'query', side_effect=[
+                [{'brand': '正常品牌'}],
+                [],
+                [{'cnt': 0}],
+        ]):
+            response = self.client.get('/api/products/filters?scope=active')
+
+        self.assertEqual(response.get_json()['data']['brands'], ['正常品牌'])
+
 
 if __name__ == '__main__':
     unittest.main()