本論文是探討同住一屋簷下的手足有學業表現差異時，父母基於要讓成績較差的孩子有進步動力與仿效對象，會對孩子說出比較話語（即明白指出優者和劣者，且要求劣者向優者學習的話），而對受比較者的影響。此種手足比較形式有別於西方社會常見的主動社會比較與被動-強迫式比較，乃命名之為「被動-第三者比較」。在上述前提下，研究者關心的問題有三個：（1）父母說比較話語的現實面（2）孩子在被動-第三者比較情境產生的認知和情緒反應（3）孩子在被動-第三者比較情境產生的認知、情緒反應與手足關係。研究者藉由Tesser理論形成相關假設，再加入華人文化的特色，期待研究結果貼近本土現象。 本文共有兩個研究。研究一，採取問卷調查法（家中手足比較現象調查表）和訪談法，施測於國小生、國中生和高職生，以瞭解父母說比較話語和比較向度之盛行率、被動-第三者比較的話語內容和情境與優者和劣者的認知、情緒反應。研究二，利用研究一的訪談結果修改原先問卷，施測於國小生和國中生，進一步瞭解一般孩子於被動-第三者比較情境產生的認知和情緒反應，與被動-第三者比較情境產生的認知、情緒反應與手足關係。發現如下的重要研究結果： 1約有七成的孩子曾聽父母說過被動-第三者比較話語。 2「學業表現」和「行為規矩」是最常被比較的向度。 3父母比較話語的多數內涵均是「明白指出優者，明白指出劣者，且要求劣者要學習優者」。 4孩子於被動-第三者比較情境產生的認知與情緒反應，較西方測量的項目多。 4優者表現出「勝不驕」的華人文化特色。 5研究結果符合Tesser理論，均是優者越感到得意，手足關係越差，劣者則是越感到生氣，手足關係越差。 6但是，若以具華人文化特色的認知和情緒反應預測手足關係，則研究結果呈現不同面貌。認知反應方面，孩子越接納父母的價值觀，且嫉妒手足擁有好的親子關係與學業表現，則比較訊息可能對手足關係不具威脅性。情緒反應方面，當孩子感到越強烈的他人焦點情緒，則比較訊息可能對手足關係較不具威脅性。研究者從文化二元論觀點解釋這個現象。並依據研究結果提供在應用層面和未來研究方向的建議。 / In Taiwan, parents used to compare their children’s academic performance with each other. The comparison includes “who is better in academic performance”, “who is worst in academic performance”, and “demanding the children who did poorly to learn their sibling who did better in academic performance”. Such comparison is different from social comparison and forced comparison, because the subject of the comparison is parent and the object of the comparison is children. And then, it is named passive-third comparison . In this thesis, I studied three questions. First, to investigate the prevalence of the passive-third comparison. And then, to understand children’s emotion and cognition in the passive-third comparison. In the last, how children’s emotion and cognition in the passive-third comparison to influence sibling’s relationship. I take self-evaluation maintenance model to explore these questions. Moreover, I conducted two studies to test the hypothesis. There are three main findings. First, the passive-third comparison in Taiwan are high prevalence. Second, children in the passive-third comparison feel more other-focused emotion(eg. shame and embarrassed) and think of other-focused thought. The last is children’s emotion and cognition in the passive-third comparison could influence sibling relationship. However, the findings are different from the past studies in USA. Therefore, to discuss these findings are from culture view.