This paper aims to clarify the role of the concept of “virtue”（徳）in Mingei theory（民藝論，the theory for Japanese folk crafts）proposed by Muneyoshi Yanagi（柳宗悦，1889–1961）. Yanagi regarded his Mingei theory not as mere criticism but as the theory or study of value（価値学）, and he believed that it belonged to aesthetics as a domain of philosophy. Therefore, he argued that Mingei theory related to the problem of the norm for beauty. The first section of this paper discusses Yanagi’s vision of Mingei theory as an alternative to modern aesthetics in which fine arts and genius artists alone were valued and everyday life was disregarded. The second section focuses on the concept of “virtue,” which interacts closely with beauty in Yanagi’s theory; specifically, the idea that has “virtue” as a basis can imbue Mingei crafts with beauty. The final section discusses how “virtue” works on aesthetic judgement with reference to the nature of things and the morals of craftsmen and viewers. From the above discussion, it emerges that Yanagi saw the norm of beauty in Mingei as being concerned with the interaction of things, creators and appreciators. In this view, Mingei theory comes to prescribe how people should live or be. It can therefore be seen as a “new” form of aesthetics that shares a cross point with ethics.