Disclosed is a semiconductor memory device having a data retention operating mode. When an entry into the data retention operating mode is performed, parity information on data of the memory cells is calculated and the error correction on the memory cells is carried out at a time of an exit from the data retention operating mode, by an ECC (Error Correction Circuit). The semiconductor memory device includes means for outputting from an NC pin flag information indicating that the semiconductor memory device is the one including the data retention operating mode, that the exit processing from the data retention operating mode is under way, and that the error correction cannot be performed.