Abstract:This paper presents an endogenous growth model with Romer-type R and D process and two types of human capital accumulation process. We will introduce an inter-generational spillover of human capital due to ``local home environment externality" conceptualized by Galor and Tsiddon (1997a; 1997b) so that human capital can be accumulated by population growth in addition to by human capital investment. Depending on the intensity of the externality, the model will generate a negative relationship between the population growth rate and the per capita GDP growth rate, which is also present in the data. We also obtain a paradoxical result that home education, which potentially accelerates the accumulation of human capital without any cost, could be harmful against the economic growth rate.