Provided is a magnetic stimulator for applying magnetic stimulation to a particular portion of a subject. This magnetic stimulator includes: a magnetic field generating means including at least a stimulation coil configured to generate a dynamic magnetic field so as to apply the magnetic stimulation a coil holder operated to displace a relative position of the magnetic field generating means with respect to the particular portion of the subject a plurality of magnetic field sensors each configured to detect the magnetic field generated by the magnetic field generating means and a user interface section configured to provide instruction information based on a result of the detection of the magnetic field generated by the magnetic field generating means, the instruction information indicating an operation of displacement to be performed using the coil holder, the detection being made by the magnetic field sensors either before or during the magnetic stimulation.