Among the ritual reforms during the Hongwu reign, in the name of "using Chinese ways to abolish barbarian customs" 用夏變夷, or "restoring antiquity" 復古, the reform of clothing played an important role. Faced with popular apparel deriving from Jin and Yuan dynasties, mixing clothing styles from different ethnicities, nations, and social hierarchies, the Ming government launched a costume reform that lasted more than thirty years and involved all the social hierarchies. During this far-reaching process, the so-called "Great Ming Clothing System" 大明衣冠 was gradually established. The newly born Ming government, in manipulating the identities of various groups through the formation of a sumptuary system, obtained its cultural orthodoxy by interacting with Confucian rites. This paper will explore the details of this reform and analyse its political motivation and effects.