diff --git a/service/book.go b/service/book.go
index 686cb95..ae975e6 100644
--- a/service/book.go
+++ b/service/book.go
@@ -527,13 +527,30 @@ func (svc *BookService) UpdateBookCatIdByISBNHandler(request *request.BookUpdate
 		return nil, fmt.Errorf("没有有效的更新字段")
 	}
 
+	// 构建更新脚本，只更新传入的字段，保留现有字段
+	var scriptParts []string
+	params := make(map[string]interface{})
+
+	// 转换为 map 以便访问
+	newCatId, ok := catIdValue.(map[string]interface{})
+	if ok {
+		for key, value := range newCatId {
+			scriptParts = append(scriptParts, fmt.Sprintf("ctx._source.cat_id.%s = params.%s;", key, key))
+			params[key] = value
+		}
+	}
+
+	if len(scriptParts) == 0 {
+		return nil, fmt.Errorf("没有有效的 cat_id 字段")
+	}
+
+	script := strings.Join(scriptParts, " ")
+
 	body := map[string]interface{}{
 		"script": map[string]interface{}{
-			"source": "ctx._source.cat_id = params.cat_id;",
+			"source": script,
 			"lang":   "painless",
-			"params": map[string]interface{}{
-				"cat_id": catIdValue,
-			},
+			"params": params,
 		},
 		"query": map[string]interface{}{
 			"term": map[string]interface{}{