A nonvolatile memory includes memory blocks each including a data storage area for storing user data and a discrimination area that is provided so as to correspond to the each data storage area on a one-to-one basis and stores discriminative data indicating a writing state of data to the data storage area. The nonvolatile memory further includes a control circuit which determines the data storage area that will be a storage destination of the user data based on a relative difference relation among the discriminative data of the respective memory blocks, and changes the discriminative data of the discrimination area corresponding to the data storage area in which the user data was written to a value different from that before the writing.