This overview discusses the status of fusion energy development in the Republic of Korea. Korea studies fusion energy through research and development in 2 ways: one by performing the Korea Superconducting Tokamak Advanced Research (KSTAR) for a domestic approach and the other by participating in the international collaboration project ITER. Korea had remarkable progresses not only in KSTAR but also in the ITER project in 2016. In KSTAR, a world record of more than 70 seconds in high-performance plasma (H-mode) operation in the superconducting tokamak has been achieved. For the ITER project, toroidal field conductors have been successfully accomplished and the other major equipment such as vacuum vessel sectors, ports, and assembly tooling seem to be reaching an end. This paper deals with current research and development results on both fields of KSTAR study and ITER project progress.