A semiconductor memory device, in which a multi-bit region including multi-bit memory cells that store data of two or more bits and a region including memory cells that store data of bits that are less than the bits of the data stored in the multi-bit memory cells are installed, is provided, which can perform a high-speed writing and lengthen the life span of the product without increasing the storage capacity of the region of the memory cells storing the data of bits that are less than the bits of the data in the multi-bit memory cells. The semiconductor memory device includes a plurality of memory cells which store n-bit (where n is a natural number that is equal to or larger than 2) data for one cell. Among the plurality of memory cells, h-bit (h≦n) data is stored in a memory MLC of a first region MLB, and i-bit (i