Provided is an information updating apparatus that suppresses performance deterioration due to switching between writable recording areas in which information elements are to be written and readable recording areas from which the information elements are to be read. Also, the information updating apparatus updates a plurality of information elements recorded in a non-volatile recording medium with robustness against power discontinuity ensured. In order to achieve such effects, two groups of recording areas that are identical in number are allocated in the recording medium. The information elements are written in either group of the recording areas indicated by judgment information as the writable recording areas. Each time all the information elements have been written, the judgment information is updated. Thus, the writable recording areas are switched between the two groups of the recording areas.