This chapter aims to clarify the nature of high-skill migration and its relationship with postsecondary education in the Association of Southeast Asian Nations (ASEAN) countries empirically using the latest available datasets for 1990 and 2000. The results show that intra-ASEAN migration was responsible for the lowest proportion of high-skill migration and the second highest concentration of bilateral corridors among four regional communities. Postsecondary-educated human capital stock in the origin but not in the destination countries explains high-skill intra-ASEAN migration. However, bilateral high-skill intra-ASEAN mobility explains postsecondary-educated human capital stock in both origin and destination countries; therefore, high-skill mobility of ASEAN could have positive relationship with increase in investment of postsecondary education in origin countries. These results indicate the necessity to encourage high-skill intra-ASEAN migration because of its effect on postsecondary education.