To provide an information storage medium having high versatility among various kinds of information equipment for accesses to stored data while retaining data protecting function to illicit access.

In the access to stored data in a memory card 10 from a host equipment side with the memory card 10 installed therein, the unique password of the memory card 10 is confirmed by an access right authentication part 16, whereby each access right (read, write, delete) is given thereto. When the read access right is not given, storage data in storage areas corresponding to each address value are successively read from the storage data in the storage area corresponding to an initial address value, and when the read data quantity reaches a prescribed value, a dummy data output part 18 outputs meaningless dummy data.