An optical disk drive which discriminates whether a light spot is incident on a groove or on an area therebetween by eliminating a pulse that appears in a binary envelope signal when the light spot passes a level section. The elimination is carried out based on an ODF section detecting signal, the ODF section detecting signal being a level section detecting signal which is produced by detecting a level section (ODF section) of the optical disk. The detection is carried out by differentiating an envelope signal, which is the envelope of an electric signal corresponding to the amount of light reflected from the optical disk. Accordingly, even if the optical disk in use has interrupted grooves, the optical head can be accurately moved to a desired track located on a land or on a groove.