A word line driving method is for a nonvolatile memory device including a plurality of memory blocks having a plurality of strings which is formed in a direction perpendicular to a substrate and connected between bit lines and a common source line. The method includes applying an offset pulse to a word line for a predetermined time to shorten a word line setting time, and applying a target pulse having a level which is higher or lower than a level of the offset pulse to the word line after the predetermined time.