Disclosed is a wavelength multiplexing optical recording apparatus comprising laser sources radiating a plurality of laser beams of different wavelengths, an optical system for focusing the laser beams, and an optical recording medium having a plurality of optical recording layers with wavelength sensitivities for selective recording by said laser beams focused by said optical system. The optical recording layers of recording medium are laminated with distances between adjacent layers being made consistent with biased focal positions of the laser beams attributable to the chromatic aberration of the optical system, so that the laser beams are focused on the optical recording layers of corresponding wavelength sensitivities.