To provide a new data erasure method allowing prevention of leakage of data by perfectly erasing secret information of a user recorded in an information apparatus such as a cellphone at high speed when reusing and recycling the information apparatus, and to provide the information apparatus and a cellphone terminal using the same.

An erasure command wherein a partition number that is an erasure target is designated is issued from a host to a NAND type flash memory device. A control part of a device interprets an address of an erasure target area specified by the partition number in reference to a partition map generated associatively to a partition table, and erases all pieces of data stored in an erasure target partition based on the interpretation.