Provided is an error-correcting decoder including: a syndrome generation unit for calculating, as a syndrome, coefficients of a residual polynomial that are obtained by dividing received data by a generator polynomial; information bit error pattern generation unit for generating all error patterns of information bits; a check bit error pattern generation unit for calculating, for each of the error patterns of the information bits, an error pattern of check bits based on the syndrome value; and an error correction unit for correcting the error pattern generated for a combination of codes having a weight of the error patterns of the information bits and the check bits smaller than a threshold value.