A high density disc having a data area which is set such that compatibility is secured in the same drive while maintaining a superior recording/reproducing feature, is disclosed.The high density disc has a center hole, a clamping area, a data area where user data is recorded, a lead in area located at the inner side of the data area, and a lead out area located at the outer side of the data area. In the high density disc in which the diameter of the center hole is 10 mm or more, the inner diameter of the clamping area is characteristically within a range of 20 26 mm. Also, the inner diameter of the data area is characteristically within a range of 35 40 mm.Therefore, while a conventional disc drive is still used, the size of the high density disc decreases and a recording capacity can be increased.