This paper shows that people lay special emphasis on difference aspects of “cooperative principle” or “politeness principle” in the light of their own culture in cross-culture communication. And it analyses what the differences of PP in the language using in Pragmatic are, and why? It deals with the differences between English and Chinese cultures. This paper shows that people lay special emphasis on difference aspects of “cooperative principle ” or “politeness principle ” in the light of their own culture in cross-culture communication. And it analyzes what the differences of PP in the language using in Pragmatic are, and why? It deals with the differences between English and Chinese cultures.