This paper discusses the political significance of women’s surname change in Japan by reviewing the history of the surname system and its establishment in the traditional family system, ie. It was created based on the idea that women belong primarily to the husband’s family and her identity is absorbed into the husband. It has significant ramifications on women’s citizenship today, when a greater number of married women are in paid employment and professional careers. The enforcement of a single surname plays a central role in sustaining the patriarchal nature of family that continues to marginalize women’s participation as equal individual citizens beyond their households.