Abstract: Asynchronous circuits have drawn increasing attentions from not only researchers in universities but also designers in corporations for their advantages in terms of no clock skew,high modularity,low power and better EMI.Design methods are critical in the researches of asynchronous circuits.In this paper,we divide the history of asynchronous circuit design into 3 stages,and in particular we give a review of the last stage.We classify the methods in the last stage into 3 classes by the specification style and the granularity of circuits: the syntax-driven method,the synchronous-to-asynchronous circuits conversion method and the full-custom based design method of fine-grain asynchronous pipelines.Design methods are then surveyed and compared from several aspects.Those aspects include theory foundation,design style,design automation,and the efficiency of designed circuits.Finally,developing trends of asynchronous circuit design methods are given.