A method of controlling magnetic recording in a magnetic recording medium and a control device for the same provides a symmetrical transferred signal waveform of equal magnitude with good reproducibility and performs magnetic transfer with high reliability. In performing initial magnetization prior to performing transfer magnetization, an AC magnetic field, the polarity of which changes in the perpendicular direction Y (or both in the perpendicular direction Y and parallel direction X), is applied to the recording surface of the magnetic recording layer of a magnetic recording medium, and the intensity of the AC magnetic field is gradually decreased with time, to demagnetize the entire magnetic recording layer.