First, a recording magnetic field is generated by a magnetic head using a coil drive current a.sub.1, and a first data signal is recorded on a groove of a recording layer of a magneto-optical disk. Thereafter, similarly, a second data signal is recorded on the same groove as above by a coil drive current a.sub.2. In this case, the first and second data signals have different signal frequencies which do not overlap each other. The amplitude A.sub.1 of the coil drive current a.sub.1, is set greater than the amplitude A.sub.2 of the coil drive current a.sub.2. This arrangement permits multiple recording and increases the recording capacity of the magneto-optical disk.