A data storage device configured to perform data storage control, comprising: a memory having a plurality of storage blocks each provided with an actual data area storing therein actual data, the memory not being able to overwrite data, and the memory being configured to erase data in units of the storage blocks when the data are erased therefrom; and a memory control unit configured to perform control of at least one of writing and reading with respect to the memory, wherein a management data area, partitioned into subregions for storing therein respective ones of a plurality of types of management data for management, is provided in the memory, the management data area being configured to store in respective ones of the subregions therein: (i) writing-in-progress management data at a time when writing of actual data starts, (ii) validity management data at a time when the writing of the actual data is completed, (iii) pre-erasure management data at a time when stored actual data is in an erasable state and erasure of the actual data starts, and (iv) completion-of-erasure management data when the actual data is erased and the storage block is not yet in an initial state; the management data area being configured to erase writing-in-progress management data, validity management data, pre-erasure management data, and completion-of-erasure management data when the actual data is erased and the storage block is not yet in an initial state, and the memory control unit being operable to determine that a storage block having validity management data, writing-in-progress management data and completion-of-erasure management data stored in the management data area and being in a valid state is a storage block having the latest data. a memory having a plurality of storage blocks each provided with an actual data area storing therein actual data, the memory not being able to overwrite data, and the memory being configured to erase data in units of the storage blocks when the data are erased therefrom; and a memory control unit configured to perform control of at least one of writing and reading with respect to the memory, wherein a management data area, partitioned into subregions for storing therein respective ones of a plurality of types of management data for management, is provided in the memory, the management data area being configured to store in respective ones of the subregions therein: (i) writing-in-progress management data at a time when writing of actual data starts, (ii) validity management data at a time when the writing of the actual data is completed, (iii) pre-erasure management data at a time when stored actual data is in an erasable state and erasure of the actual data starts, and (iv) completion-of-erasure management data when the actual data is erased and the storage block is not yet in an initial state; (i) writing-in-progress management data at a time when writing of actual data starts, (ii) validity management data at a time when the writing of the actual data is completed, (iii) pre-erasure management data at a time when stored actual data is in an erasable state and erasure of the actual data starts, and (iv) completion-of-erasure management data when the actual data is erased and the storage block is not yet in an initial state; the management data area being configured to erase writing-in-progress management data, validity management data, pre-erasure management data, and completion-of-erasure management data when the actual data is erased and the storage block is not yet in an initial state, and the memory control unit being operable to determine that a storage block having validity management data, writing-in-progress management data and completion-of-erasure management data stored in the management data area and being in a valid state is a storage block having the latest data.