As a type of intimate architecture, fashion has always mediated the dialogue between clothes and the body, or fashion and figure. This study seeks to inquire the current aesthetic consciousness of the body and dress in Japanese avant-garde fashion and intends to research the features and meanings in the pastiche of Western sartorial convention in Japanese avant-garde fashion in order to examine the changing aesthetic attitude in postmodern fashion. The study investigates subjects of the fashion collections of the turn of the twenty-first century, when pastiche strategies frequently appeared in Japanese avant-garde fashion, through the methodology of literature research and case analysis. The results of the study are as follows: by developing the strategy of pastiche, Japanese avant-garde fashion exposes the defectiveness of the Western idea of the idealized and standardized body for mass productions, thus freeing design from its traditional confinement to the human body. Drawing on the re-conceptualization of the sartorial convention of Western tradition, Japanese avant-garde fashion designers tend to experiment with extreme exaggeration in form, refusing to subscribe to the traditional Western values built on the balance and symmetry of the body. Through the combination of the past and the present as well as the inner-wear as outerwear strategy, the historical pastiche challenges convention and symbolism, which results in the discord between signifiant and signifié of clothing.