An optical pickup includes an optical system in which light from a light source is introduced through an objective lens into an optical recording medium and in which light reflected from the optical recording medium is introduced into a light-receiving unit and an objective lens driving unit for driving the objective lens based on a light output detected at said light-receiving unit. In this optical pickup, a diffraction element is provided between the light source and the objective lens, the diffraction element is provided with at least first and second diffraction areas and the first and second diffraction areas have such grating shapes that ± first-order diffracted lights diffracted are received by the light-receiving unit at the position in which 0-th order light and ± first-order diffracted lights generated from guide grooves of the optical recording medium may not overlap with each other.