Abstract: Using the database provided by China Family Panel Survey(CFPS)2010,this paper not only analyzed the influence of family planning policy on urban-rural income gap,but also Oaxaca-Blinder decomposition method and RIF regression decomposition method are used to measure the contribution of family planning policy to urban and rural income gap. The result shows that:(1) the family planning policy is conducive to improvement of children's income, and the marginal effect of income on urban is greater than that of rural; (2) the policy allows for more births is not conducive to improvement of rural children's income. It will significantly lower the income of the children if family super living, and the negative impact on urban is greater than that of rural; (3) the family planning policy presents a u-shaped thrust on urban-rural income gap, the role of low-income and high-income groups is large but relatively small for middle-income groups. Therefore, the family planning policy should coordinate the overall situation, take measures according to local conditions, reward and punish both, improve the level of human capital in rural areas and the quality of education of children, and promote the convergence of fertility rate and human capital level of urban and rural residents.

Key words: family planning policy, urban-rural income gap, oaxaca-blinder decomposition, RIF regression decomposition, offsprings' income