diff --git a/app/module/article_categories/mapper/article_categories.mapper.go b/app/module/article_categories/mapper/article_categories.mapper.go
index 88d3606..205c0c2 100644
--- a/app/module/article_categories/mapper/article_categories.mapper.go
+++ b/app/module/article_categories/mapper/article_categories.mapper.go
@@ -13,7 +13,7 @@ func ArticleCategoriesResponseMapper(articleCategoriesReq *entity.ArticleCategor
 			Title:         articleCategoriesReq.Title,
 			Description:   articleCategoriesReq.Description,
 			ThumbnailPath: articleCategoriesReq.ThumbnailPath,
-			ThumbnailUrl:  "/article-categories/thumbnail/viewer" + strconv.Itoa(int(articleCategoriesReq.ID)),
+			ThumbnailUrl:  "/article-categories/thumbnail/viewer/" + strconv.Itoa(int(articleCategoriesReq.ID)),
 			ParentId:      articleCategoriesReq.ParentId,
 			CreatedById:   articleCategoriesReq.CreatedById,
 			StatusId:      articleCategoriesReq.StatusId,