An optical disk apparatus according to the present invention is capable of reading data from an optical disk 102 which has a plurality of information recording layers, including a first information recording layer whose distance from a disk surface is relatively small and a second information recording layer whose distance from the disk surface is relatively large. This optical disk apparatus includes: a focus control section 117 for causing a converging point of the light beam to be positioned on an arbitrary information recording layer of the optical disk 102; a tracking control section 118 for causing the converging point of the light beam to be positioned on a predetermined track of the information recording layer; and a gain switching section 108 capable of changing gain characteristics of at least one of the focus control section 117 and the tracking control section 118. The gain switching section 108 prescribes a gain crossover frequency when reading data from the first information recording layer to be a value which is lower than a gain crossover frequency when reading data from the second information recording layer.