A magnetic stimulator includes a coil which applies magnetic stimulation to a head of a living body, an intensity controller which controls an intensity of the magnetic stimulation applied by the coil, an acquiring section which acquires a biological signal from the living body, a detector which detects an adverse event of the living body from the biological signal acquired by the acquiring section, and an intensity suppressing section which, when an adverse event of the living body is detected by the detector, suppresses the intensity of the magnetic stimulation that is controlled by the intensity controller.