The present invention provides a recording/reproduction device that can perform post-record editing on a disk on which post-record editing has been determined to be impossible by conventional methods, and that can reproduce data that thus has been subjected to post-record editing, by devising a method for access in one cycle of repetitive processes of post-record editing. The recording/reproduction device is provided with a pick-up for recording or reproducing information and a control portion for controlling an operation of the pick-up, in which when reproduction is performed from an information recording medium on which in a separate area from a main sequence in which data blocks including original audio data and video data are recorded in succession, an additional sequence in which data blocks including post-record audio data are recorded in succession is formed, the control portion controls an operation of the pick-up in such a manner that the pick-up accesses the main sequence and the additional sequence alternately, and reproduces a plurality of data blocks in succession in each access.