Embodiments of the invention provide a magnetic disk drive that does not generate errors when information is read even if considerable time has elapsed after the information was written on the magnetic disk. In one embodiment, a magnetic disk has a storage area divided into a plurality of sectors ST1. Time stamps TP1 corresponding to each sector data m1 stored in the sectors ST1 are stored in a time stamp recording medium. A processor controls the magnetic disk drive to read time stamps TP2 of sector data m2 stored in any sectors ST2 of the sectors ST1 and refresh sector data m3 selected based on an elapsed time calculated from information about the time when the time stamps are read and the time stamps TP2.