A memory system includes: an ECC unit suitable for generating third data by correcting second data and a third DBI flag by correcting a second DBI flag, based on the second data, the second DBI flag, and a second parity, which are provided through a channel; a DBI unit suitable for generating fourth data by determining whether a plurality of third data bits respectively corresponding to a plurality of DBI flag bits constituting the third DBI flag are inverted, based on the third data and the third DBI flag; and a DM unit suitable for generating a DM flag indicating whether a write operation is performed on a plurality of fourth data bits constituting the fourth data, based on the second data.