Contents data that have been enciphered and transmitted are recorded as they are on a recording medium, and the contents key used to encipher these data is enciphered in a way used in this recording system and is recorded on the medium. Moreover, a step is taken to ensure that fine trick plays can be performed. In recording contents data that have been enciphered and transmitted, the contents data themselves are recorded in the enciphered state on the recording medium. However, the contents data are decoded by a contents data decoding circuit 46, and a map file containing necessary management information for reproduction is created by a map file creating circuit 47 and this file is recorded together with the contents data.