The majority of current studies about descendants of rural migrants focus on school education，but few concern the labor market.Base on the sample survey data from Nanjing，this paper finds that,the social and economic status of descendants of rural migrants is higher than those without migration experience,but lower than urban residents.With the improved Oaxaca-Blinder decomposition，this paper explores how the income differentials are influenced by human capital，social capital and household registration discrimination. The result shows that human capital is the most important factor. Household registration discrimination and social capital are also the differentials.