A nonvolatile memory device using interleaving technology is provided. The nonvolatile memory device includes a first controller configured to allocate one of 2N threshold voltage states to N-bit data where N is 2 or a natural number greater than 2, a second controller configured to set a difference between adjacent threshold voltage states among the 2N threshold voltage states so that the difference increases as a threshold voltage increases, and a programming unit configured to form a threshold voltage distribution state corresponding to the allocated threshold voltage state and to program the N-bit data to a multi-level cell. The second controller controls the difference between the adjacent threshold voltage states to equalize the number of read errors for all intersections among the 2N threshold voltage states at the end of life.