In this paper, I want to analize the changing process of Japanese "Ie" from the viewpoint of kinship organization. Some researchers in Japan proposed following hypotheses : 1) Dozokudan (the social group that is composed of several "Ie"s) and Shinrui (the social relation between "Ie"s that is formed by the marriage of its membership) can be explained by the kinship theory, and that 2) the functional importance shifts from the former to the latter in the process of industrialization and urbanization. Now, this area is developing rapidly, because many peoples (households) have moved into this rural district, after a private railway was laid to Tokyo in 1966. And it is made clear by this investigation that functional importance of "Ie", Dozokudan and neighbourhood groups are still maintained. It follows that Dozokudan must not be included in kinship group. It is rather a special sort of social group whose cohesiveness has depended on the productivity of this rural village.