To provide a one time-nonwritable/nonerasable optical disk, which enables the recording verification and the editing and correction of data, and a using method therefor.

The phase transition type optical disk is constituted so that the time required for the crystallization of a recording layer 4 is adjusted so as to be long compared with the time for a laser spot to pass through a recording layer 4 at the time of operation at the linear velocity equivalent to the actual time recording, and the time required for the crystallization of a recording layer 4 is adjusted so as to be short compared with the time for a laser spot to pass through a recording layer 4 at the time of operation at the linear velocity slower than the linear velocity equivalent to the actual time recording. Further, one time-nonwritable/nonerasable operation is executed at the time of the actual time recording, and the rewritable operation is executed at the time of recording at a velocity slower than dealing with the actual time.