This paper studies the intergenerational income flow from the present situation of income distribution gap in China. In order to promote the reasonable flow of intergenerational mobility, this paper makes education as an important factor to promote intergenerational mobility of income according to the theory of human capital education, and expect to explore the impact of education investment structure on intergenerational mobility. By constructing a three-stage OLG model with family education investment and government education investment, this paper makes a detailed distinction between the human capital investment in basic education and higher education, carrying out the policy experiment on the change of government education investment structure, and we analyze the different education investment structure of urban residents under the intergenerational changes in the flow of income in order to find the best policy to ease intergenerational income flows. Through numerical simulation, the findings of this paper are as follows: first of all, controlling the government investment in education, increasing the proportion of basic education investment can reduce the income of the Gini coefficient and improve the income distribution. Secondly, the control of government investment in education, increasing the proportion of government investment in basic education, the intergenerational mobility will increase. And not only the probability of upward mobility increases, but also the probability of downward flow increases. Finally, family education investment and family income have a clear positive correlation.