To provide an optical disk recording and reproducing apparatus capable of reproducing a valid recorded video data even when recording quality of a management information recording part is low, resulting in read failure.

The optical disk recording and reproducing apparatus having a function of recording a video to a write-once optical disk is provided with system controllers 39, 53 which update and write content management information, which is management information of recorded video content data, at each recording operation and copy this written and updated content management information in an area reserved beforehand in an optical disk inner circumferential part, thereby recording a disk format compatible with ROM media, forming and recording disk management information based on the content management information, managing access information to data in fragment units contained in the disk management information, and controlling the update in fragment units in association with update of the video content data.