The present invention provides a data storage device comprising a disk storage medium containing user data in a plurality of sectors, a head for writing or reading the user data and error correcting means for correcting an error that occurs in the user data during the reading process. The error correcting means comprises a syndrome generator for generating syndromes on the basis of the user data contained in predetermined sectors, registers for storing the syndromes generated and an exclusive OR circuit for exclusive ORing the values stored in the registers.