A semiconductor memory device includes a memory cell unit including a plurality of blocks, each of the blocks including a plurality of pages, and a circuit configured to count a number of activated or non-activated memory cells in one or more pages when a first voltage is applied to gates of memory cells of said one or more pages to read data therefrom, count a number of activated or non-activated memory cells in said one or more pages when a second voltage different from the first voltage is applied to the gates of the memory cells of said one or more pages to read data therefrom, compare the counted numbers, and store, in a register, data about deterioration of the memory cells of said one or more pages depending on a comparison result.