Abstract：In the term of economics, so-called “Familism” is that family is as the basic unit to calculate costs and benefits. The fundamental difference between traditional Chinese society and modern Western society is that the former is a familist society, while the latter is an individualist one. A familist approach to economics has two important differences from the individualist approach: (1) Familism regards lifetimes as unlimited, while individualism regards life as limited; (2) Familism regards individuals as members of a family who are not independent and equal with each other, while individualism describes individuals who are independent and equal with each other. Most conclusions change a lot if we do not accept individualist assumptions. Calculating costs and benefits of each family as a unit, the maximization of family benefit is not only the sum of the benefits of the members of the family as individuals; and the preservation of a family over time plays a more important role in raising family utility, which aggregates as time passing. Familism explains many distinctive features of Chinese traditional society, including aspects of its unique economic, political and cultural structures. Such a familist approach will expand the territory of economics and provide new accounts of Chinese, even world, history.