Abstract: Family is the basic unit of social composition, and the family structure affects the overall social and economic development of the population through its direct effect on family relations and family functions. Based on the data of previous national surveys, this paper comprehensively describes the overall situation and prominent characteristics of family structure changes in Japan from 1960 to 2020, and systematically analyzes the dynamic mechanism of family structure changes and its impact on Japan’s population, social development, and economic development. The findings are as follows. Firstly, while the total number of Japanese households continues to expand, the average size of the households keeps shrinking. Secondly, the overall trends of Japanese family household structure include the stability of nuclear families, the decline of stem families and the rise of single households. Lastly, the overall characteristics of the change of nuclear families include the shrinkage of the standard nuclear families, the expansion of the nuclear families consisting of only one couple and the slight increase of singleparent nuclear families. The author believes that the multiple driving forces of Japanese family structure change are demographic, economic, social, and cultural causes including subreplacement fertility and aging population, stagnation of economic development and increase of female labor force participation rate, collapse of family system and equality of the family system, and the trend of staying single and emancipation of women’s mind. The changes of Japanese family structure have a profound impact on its population, social, economic, and cultural development.

Key words: family structure, change, Japan, driving force