Plasma consists of a huge number of charged particle. The various behaviors of plasma brought about by the interaction between charged particles and the electromagnetic field are complex nonlinear problems. In order to clarify and predict the nonlinear phenomena of plasmas, we promote large-scale computer simulations using supercomputers.Our primary research subject is the interaction between fast ions and magnetohydrodynamic (MHD) waves in magnetically confined fusion plasmas. This is an especially important subject for ITER, which is under construction in France with the international collaboration. In addition, we conduct simulation studies of energetic particles and MHD phenomena, and develop computational physics models and high-performance computing methods. We also actively promote both domestic and international collaborations for many experiment devices. (Google Scholar: Yasushi Todo, ORCID: 0000-0001-9323-8285)