A read method of a multi-level cell memory device includes receiving a first read command, and reading first and second hard decision data by performing first and second hard decision read operations using a first hard decision read voltage and a second hard decision read voltage, respectively, the second hard decision read voltage being higher than the first hard decision read voltage. The method further includes selecting one of the first and second hard decision read voltages, reading first soft decision data by performing a first soft decision read operation using a plurality of soft decision read voltages having voltage levels which are different from that of the selected one of the first and second hard decision read voltages, and providing the first soft decision data to a memory controller for first error correction code (ECC) decoding.