Dialogues ,a common writing method ,which writers shape the characters ,express their minds , lead their behavior or develop the plot of the story ,and they are the key part of literary works .Discourse Analysis provides translators with a fine perspective to understand and translate dialogues .With reference to Water Margin and Sidney Shapiro’s version ,key dialogues in Water Margin and its English version are analyzed with cooperative principle ,politeness principle and conversational implicature ,so as to provide a n...