An operator is prevented from touching terminals and the like. A reactor includes an outer peripheral iron core, and at least three core coils disposed inside the outer peripheral iron core. Each of the core coils includes a core and a coil wound onto the core. The reactor further includes a terminal base that has a plurality of terminals connected to leads extending from the coils and is disposed on one end of the outer peripheral iron core, and an electric shock prevention cover for covering the terminals of the terminal base.