The crossover in fashion refers to the coordination of different items, each with a different atmosphere. In a broad sense, it is the mutual exchange across the existing areas, that is, the creation of a new style by disparate and opposite elements coexisting in a look. This paper studies typical features of the crossover shown in modern fashion based on sub-culture by examining the concept and formation factors of the crossover through social aspects rather than particular art modes to predict the current fashion and suggest a new direction. Crossover fashion appeared in social and cultural environments, has four characteristics : the visual discordance of sexes, the appearance of the lingerie look, the mixture of folk style, and the appearance of the reactionary mode. The crossover, appeared in sub-cultures and diffused into the public, may be considered the creation of a new sense of beauty and a possibility for the future. It is expected to keep expanding ifs range in fashion, since it is an expression of human will to restore liberal sensibility not confined to formality.