diff --git a/inventory-backend/app/api/v1/import_api.py b/inventory-backend/app/api/v1/import_api.py
index 842e5ad..9e4b453 100644
--- a/inventory-backend/app/api/v1/import_api.py
+++ b/inventory-backend/app/api/v1/import_api.py
@@ -47,9 +47,16 @@ def download_template():
 @jwt_required()
 @permission_required('material_list:operation')
 def preview_import():
-    """Dry-Run 预览 + 验证（不写入数据库）"""
+    """Dry-Run 预览 + 验证（不写入数据库）
+
+    FormData:
+        type: 'material' | 'bom'
+        file: Excel 文件
+        mode: 'skip' (默认) | 'update' — update 模式下 DB 重复行显示为「将被更新」而非错误
+    """
     try:
         import_type = request.form.get('type', 'material').strip()
+        mode = request.form.get('mode', 'skip').strip()
         file = request.files.get('file')
         if not file:
             return jsonify({'code': 400, 'msg': '请上传文件'}), 400
@@ -60,11 +67,11 @@ def preview_import():
         from io import BytesIO
 
         if import_type == 'material':
-            results = preview_material(BytesIO(file_stream))
+            results = preview_material(BytesIO(file_stream), mode=mode)
         else:
             results = preview_bom(BytesIO(file_stream))
 
-        success_count = sum(1 for r in results if r['status'] == 'success')
+        success_count = sum(1 for r in results if r['status'] in ('success', 'update'))
         error_count = sum(1 for r in results if r['status'] == 'error')
 
         return jsonify({
@@ -85,24 +92,33 @@ def preview_import():
 @jwt_required()
 @permission_required('material_list:operation')
 def execute_import():
-    """确认导入执行（事务保护）"""
+    """确认导入执行
+
+    Body:
+        type: 'material' | 'bom'
+        rows: 待导入行列表
+        mode: 'skip' (跳过重复，默认) | 'update' (覆盖更新已有记录)
+    """
     try:
         data = request.get_json() or {}
         import_type = data.get('type', 'material').strip()
         rows = data.get('rows', [])
+        mode = data.get('mode', 'skip').strip()
 
         if not rows:
             return jsonify({'code': 400, 'msg': '导入数据不能为空'}), 400
         if import_type not in ('material', 'bom'):
             return jsonify({'code': 400, 'msg': 'type 必须为 material 或 bom'}), 400
+        if mode not in ('skip', 'update'):
+            return jsonify({'code': 400, 'msg': 'mode 必须为 skip 或 update'}), 400
 
-        # 仅导入状态为 success 的行
-        valid_rows = [r for r in rows if r.get('status') == 'success']
+        # 仅导入状态为 success 或 update 的行，error 行不参与导入
+        valid_rows = [r for r in rows if r.get('status') in ('success', 'update')]
         if not valid_rows:
-            return jsonify({'code': 400, 'msg': '没有可导入的有效数据（全部为error状态）'}), 400
+            return jsonify({'code': 400, 'msg': '没有可导入的有效数据'}), 400
 
         if import_type == 'material':
-            result = execute_material_import(valid_rows)
+            result = execute_material_import(valid_rows, mode=mode)
         else:
             result = execute_bom_import(valid_rows)