An optical disc has a wobble pregroove which continues in a circumferential direction of the optical disc and wobbles in a radial direction of the optical disc such that the wobble pregroove meanders around a mean center line of meandering. Information recording process is performed by the steps of irradiating an optical beam along the wobble pregroove to form pits, thereby recording information in the form of the pits, and controlling the recording of the information in accordance with a radial distance of the wobble pregroove relative to the mean center line of meandering. Information reproducing process is performed by the steps of irradiating an optical beam along the wobble pregroove to optically detect pits which are formed along the wobble pregroove, thereby reproducing information in the form of the detected pits, and controlling the reproducing of the information in accordance with a radial distance of the wobble pregroove relative to the mean center line of meandering.