A nonvolatile memory device includes a memory cell array, an address decoder, an input/output circuit, a CSL driver, and control logic. The memory cell array includes a plurality of memory blocks each having a plurality of strings that are formed in a direction perpendicular to a substrate and are connected between bit lines and a common source line. The CSL driver sets up the common source line with a predetermined voltage and supplies or drains charge to or from the common source line using a voltage level of the common source line as a feedback signal.