Leech认为,礼貌原则是对合作原则的有益补充,它向我们解释了为什么人们说话通常都不那么直接,而是暗示他们的含义。礼貌原则包括六条原则,简述了说话的一些技巧,其中第一条原则--策略准则是最重要的,是对其它原则的总概括。礼貌原则的作用在于能够使谈话人之间保持一种友好关系而使谈话进行得顺利。然而,世界上的一切事物都是相对的,在实际应用中,由于各国、各地区的文化背景差异及语言的差别,人们对“礼貌”常常有不同的理解,这样就导致了跨文化交际中的障碍。本文主要论述了礼貌原则产生的原因、内容及其用法,并例举了一部分中外文化中对“礼貌”理解的差异,旨在帮助广大英语爱好者在掌握语法知识的基础上,能够用英语进行有效的交际。 Leech believes that the politeness principle is a useful complement to the principle of cooperation and explains to us why people are often less direct in their language than to imply their meaning. The politeness principle includes six principles, outlines some of the skills of speaking, of which the first principle - the principle of strategy is the most important, is the general summary of other principles. The politeness principle is to make the conversation go smoothly by maintaining a friendly relationship between the speakers. However, everything in the world is relative. In practice, people often have different understandings of “politeness ” due to different cultural backgrounds and different languages ​​in different countries and regions. This leads to cross-cultural Obstacles in communication. This paper mainly discusses the reasons, contents and usage of the principle of politeness, and also illustrates the differences in the understanding of “politeness” in a part of Chinese and foreign cultures in order to help the majority of English lovers, on the basis of grasping the knowledge of grammar, English for effective communication.