To provide a broadcast receiver configured to play back a program that another receiver received and video-recorded, and a key data sharing method for enabling such playback.

A digital broadcast receiver 11 includes: a tuner for selecting and receiving a broadcast signal of digital broadcasting; a key data generating means for generating key data specific for a recording medium or for the present receiver; and key data modifying means for modifying non-generated key data which are not generated by the key data generating means, into generated key data which are generated by the key data generating means, if such non-generated key data are recorded on the recording medium.