To provide a method for controlling a storage device, which surely prevents an error generated by a sector unit from being corrected with invalid error correction information when error correction information of a redundant sector is not rewritten.

In the method for controlling a storage device, data are written in a storage medium including a plurality of groups each constituted of a plurality of sectors and a redundant sector for storing error correction information for correcting an error of data stored in the sector for each group. The method includes: rewriting the data of the sector; and writing the invalidation data indicating that the error correction information is invalid in the redundancy sector if the error correction information stored in the redundancy sector of the one of the groups has not been rewritten.