Abstract: An optical head comprising an object lens by which a light beam from a light source is projected so as to converge onto said magneto-optical recording medium, a beam splitter disposed along an optical path between the light source and the object lens, for separating the beam emitted from the light source and a first polarized light component or a second polarized light component different therefrom of a light beam returned from the signal surface of said magneto-optical recording medium via said object lens, and a photodetector for receiving the returned beam separated by the beam splitter, wherein the separation rate of the first component or second component by the beam splitter is not less than 85% and not more than 95%. This configuration enables the optical head to be small-sized, and the returned beam is detected with high precision.