With nonvolatile memory device employing a nonvolatile memory suc h as multiple-valued NAND flash memory or the like in which each memory cell holds data in a plurality of pages, there is such a problem that, if an error occurred under writing data, data stored in other page in the same group of the current page is changed, and hence the object of the present invention is to solve this problem. In writing data into a nonvolatile memory 110, when error occurred under writing data into a certain page, an error page identification part 128 identifies an error type and a physical address of the page where error occurred. An error corrector 129 then corrects errors occurred in other pages belonging to the same group of error occurrence page.