An optimal track zero determination method used in a hard disk drive and a hard disk drive using the method. The method has the operations: (a) performing a sequential seek operation on target tracks of a disk, in units of predetermined numbers of tracks, outwardly, from a track separate from a physical track zero position obtained in a servo track write operation, by a predetermined distance toward the physical track zero position; (b) determining whether the target tracks belong to a region where a track-following operation is normally performed, and determining whether an actuator arm connected to a transducer is in contact with a mechanical buffering unit during the sequential seek operation of operation (a); and (c) selecting as a logical track zero, the target track belonging to the region where the track following operation is normally performed and the actuator arm is not in contact with the mechanical buffering unit.