Abstract: A political speech is a kind of speech about an announcement of one’s stand, a clarification of one’s view, and a propagation of assertion of countries’ internal affairs and external relations. As a means of communication, a political speech especially focuses on the usage of Politeness Principle, The thesis will compare Hu Jintao’s speech in Yale University and Obama’s speech in Cairo University so as to find the similarities and differences of the usages of Politeness Principle between Chinese and English political speeches. Both of the speakers are the head of the country, and their targeted listeners are foreign students. However, the speakers use Politeness Principle differently due to the differences of countries, culture, language, background, religions. 

Key words: Politeness Principle; Political speech; Case study

摘要：政治演讲是指人们针对国家内政事务和对外关系，表明立场、阐明观点、宣传主张的一种演讲。政治演讲作为一种交际方式尤其重视礼貌原则的运用。本文将以胡锦涛在耶鲁大学的演讲和奥巴马在开罗大学的演讲为例来探索中英政治演讲中礼貌原则运用的异同点。两位演讲者都是一国领导人，听众都是外国大学生。但由于两者文化、语言、背景、宗教信仰等方面的不同，他们在礼貌原则的运用上也有所不同。

关键词：礼貌原则；政治演讲；案例分析