There is much controversy over definition and measurement of family well-being，challenging the government’s effort to construct happy families．Based on the sampling survey data in Beijing in 2014，this paper explores the significant differences in family well-being among various family types and the possible determinants of family well-being．Taking families as the analysis unit，the paper constructs the standardized scores of family well-being and summarizes relevant variables into 7 factors as control variables．The results show that all sample families are moderately happy，and compared to the intact families，those that are sectional have statistically significantly lower scores of family well-being．However，MLRmodel denies the effect of family type on family well-being and admits the roles of member relationship factor，security level factor and spousal relationship factor．