Disclosed is an error correction system, comprising: a demodulator for receiving and demodulating raw data to generate an ECC block; an on the fly PI ECC decoder, coupled to the demodulator, for performing a PI ECC operation on the ECC block; a data buffer, for storing the ECC block; a non-linear EDC check device, for performing a non-linear EDC operation to generate an EDC result; a syndrome generator for generating at least one syndrome according to a PI codeword and a PO codeword of the ECC block; an ECC decoder for performing an ECC operation according to the syndrome; and an EDC corrector for correcting the EDC result according to a result of the ECC operation; wherein the syndrome comprises at least one of a PI syndrome and a PO syndrome, and the ECC decoder performs the ECC operation after the PI ECC operation.