A memory system according to the present invention includes, in addition to an computing device, a plurality of first blocks that are provided to store information including user information, and first physical addresses not overlapping one another are assigned to, respectively, and a plurality of second blocks that are provided to store first physical addresses of initial defect blocks out of the plurality of first blocks, respectively, wherein the computing device finds the first physical address corresponding a inputted given logical address, based on a given mirror logical address corresponding to the given logical address, and information stored in the second blocks.