This paper investigates the types of technology in international R&D spillovers and a relationship between technology levels and stages of economic development. It also examines the role of human capital in R&D spillovers. The results of this paper show that medium-high
technology is the main source of technology diffusion in developing countries, and high technology is more important in advanced countries. Furthermore, the second important technology in R&D spillovers is different across different stages of economic development: medium-low technology in the low- income group and high technology in the middle-income
group. Third, the role of high technology in R&D spillovers becomes larger as per capita income rises. These findings suggest that stage of economic development matters in the type of technology diffusion. Finally, education is also a major factor in R&D spillovers and it plays more important role in relatively higher technology level with higher stage of economic development.