Transmutation of 90Sr by inertial confinement fusion is discussed. A pellet composed of deuteriumtritium fuel surrounded by 90Sr is compressed by a laser or a particle beam. It is shown that a high transmutation rate and a small transmutation energy are obtained because of the highly compressed 90Sr, which has a large probability of a transmutation reaction. The number of cycles, including recovering and refabrication of the target, is also discussed.