Abstracts: Idiom is the crystallization of a language, as well as an integral part of a national language. With the increasingly frequent cross-cultural communication, people have begun to pay more and more attention to understand the culture of a nation from the idioms. Idioms and culture are closely related. The influence of culture on English is obvious.  When communicating without a deep understanding of its cultural background, people may get confused and make mistakes. Therefore, understanding the cultural differences by idioms in communication is very important, and understanding the differences in Chinese and English helps us to have a better learning of language. Thus, in my paper, I am going to introduce the difference of idioms from the geographical environment, religious faith, customs, historical allusion, literary works and values. And I hope that by comparing some English and Chinese idioms, we can analyze the particularity and difference of two national culture. After that, it will help us to master English national language and cultural knowledge, and make the cross-cultural communication more and more fluent.

Key words: Chinese and English idioms; cultural differences