An optical pickup apparatus is provided. Segmented regions included in a focus diffraction region includes focus segmented regions corresponding in number with different light emitted by a light source. Different focus segmented regions are arranged adjacent to each other alternately in a direction perpendicular to a parallel dividing line. Segmented regions included in a tracking diffraction region includes tracking segmented regions corresponding in number with different light emitted by the light source. Different tracking segmented regions are arranged adjacent to each other alternately in a direction perpendicular to the parallel dividing line.