According to one embodiment, a memory device includes a memory unit, a first storage unit, a second storage unit, a third storage unit, a data move unit, and a controller. The first storage unit stores a logical address and an intermediate address. The second storage unit stores the intermediate address and the physical address corresponding to the intermediate address. The third storage unit stores a flag corresponding to the logical address and the intermediate address. The flag represents whether read of latest data by a read operation has succeeded. When the flag stored in the third storage unit represents a success of the read of the latest data, the controller determines whether write has been done for the same logical address of the memory unit during the data move processing, and if the write has been done, invalidates the data move processing.