With recent achievement of the fundamental programmatic milestone by JT-60, nuclear fusion R&D activities in Japan are now more strongly focusing on the next step machine development. In 1985–1986, Nuclear Fusion Council of Atomic Energy Commission of Japan reviewed extensively the next step nuclear fusion R&D plan, and the results are reflected in the Long Term Program for Nuclear Power Development and Utilization set up by the Atomic Energy Commission in June, 1987. The present paper describes an overview of the Japanese fusion program with particular emphasis on fusion nuclear technology development.