It is possible to realize a user interface having a high degree of freedom and high power of expression in a recorded medium of a large capacity. There is provided a flag indicating whether the play item has multi-angle structure which can be reproduced by a plurality of angles. Moreover, at the head of a decode unit, there is provided a flag indicating whether it is an angle switching-enabled point. In a seamless multi-angle structure, angle switching can be performed without increasing the number of interleave units. In the non-seamless multi-angle structure, by using this flag, a predetermined area of the end side of each angle is made angle switching-disabled, so as to eliminate discontinuity of reproduction when coming out of the multi-angle. Moreover, there is provided a flag indicating whether it is possible to reproduce the sub item asynchronously with the main path so that the sub play item of audio alone can be used as BGM.