A storage device having enhanced operating efficiency includes a memory device with a plurality of memory blocks and a memory controller that performs an operation of de-randomizing data stored in different memory blocks using an identical random seed. The memory controller includes a random table that has a first address group including physical page addresses of a first memory block and a second address group including physical page addresses of a second memory block. The random table also has a random seed group that includes random seeds corresponding to the first address group and the second address group.