隨著消費者對網路使用習慣與依賴度提升，網路廣告目前在消費者端的發展日趨成熟，尤其是關鍵字廣告；因其更能精準的鎖定目標顧客，以及成本相對低廉，受到廣告主的青睞與重視，在廣告市場的規模明顯成長。近年來更有許多企業藉由搭便車(piggybacking)的關鍵字廣告方式，購買競爭對手、通路品牌或非企業本身的產品名稱等關鍵字詞組，作為自己的關鍵字廣告，增加企業廣告的曝光機會。 本研究以實驗法操弄消費者使用不同的搜尋策略，產生的搜尋結果與品牌預期一致性及類別關聯探討關鍵字廣告的效果，共計發放642份問卷經由多變量變異數分析等方法，得出研究結論如下： 1. 以產品名稱搜尋，消費者對知名品牌的廣告產品態度與廣告品牌態度明顯優於不知名品牌。 2. 以品牌名稱搜尋，消費者對與預期一致的品牌的廣告注意、正面廣告態度、廣告產品態度、廣告品牌態度皆明顯優於非預期的品牌。 3. 關鍵字廣告產品與消費者預期搜尋的產品關聯高時，則消費者對廣告注意與瞭解程度顯著高於產品類別關聯低之產品；同時，對關鍵字之正面廣告態度、產品及品牌態度皆優於產品關聯低的廣告。 4. 認知需求會增強消費者對廣告產品類別關聯高的關鍵字廣告的瞭解能力與提升對廣告產品的態度。 5. 認知需求對搜尋結果是否與預期一致或知名品牌之廣告效果的調節效果不顯著。 / As consumers are relying more and more on the internet, web advertising has become more mature on the consumers’ side, especially for keywords advertising. Advertisers have favored keywords advertising due to its ability to precisely target its customer and relatively low cost, which resulted in a significant growth in the advertising market. Recently, many companies started to use piggybacking as a keyword advertising method, buying keyword phrases of competitors, channel brands or product names to use as their own keyword advertisement, in order to increase the exposure of their corporate advertisement. This study used an experimental method to manipulate consumers using different search strategies, and investigated the influence of brand expected consistency and category relevancy. A total of 642 questionaires were analyzed by using MANCOVA analysis, and resulted in the following conclusions: 1. Search by product name: Consumers’ attitude toward advertising product and advertising brand were significantly better for well-known brands compared to unknown brands. 2. Search by brand name: Consumers’ advertising notice, attitude towards positive advertising, advertising product and advertising brand attitudes were significantly better for the expected consistency brand compared to inconsistency brands. 3. Consumers’ advertising notice, understanding, attitude towards positive advertising, advertising product and advertising brand were significantly better for highly relevant product categories compared to low relevant product categories of consumers’ search. 4. Consumers’ need for cognition enhanced the ability for consumers to understand the keyword advertising and raised their attitude towards the advertised product. 5. Consumers’ need for cognition regarding search results on the brand expected consistency or brand familiarity towards advertising effect was not significant to become a moderator.