An optical pickup including: a monolithic laser light-emitting unit for emitting a first laser beam and a second laser beam having mutually different wavelengths; an one-sided spectrally separating unit for spectrally separating the first laser beam and the second laser beam; a polarizing unit for allowing the laser beam passed through the one-sided spectrally separating unit to be introduced to an optical disk side and for reflecting reflected light from the optical disk; an astigmatism unit for imparting astigmatism to the reflected light; and a photodetecting unit in which a first laser reflected light-receiving portion is arranged in such a manner as to be offset from a second laser reflected light-receiving portion, wherein an optical system is constructed such that a long-axis direction of an ellipse indicating a light spot on the optical disk becomes oblique with respect to a tracking direction.