1. A non-volatile memory device having a vertical structure, the non-volatile memory device comprising: a substrate; a semiconductor pole formed on the substrate to extend vertically with respect to the substrate; a NAND string formed on the substrate to extend vertically with respect to the substrate and along sidewalls of the semiconductor pole, the NAND string comprising a plurality of memory cells and at least one pair of first selection transistors adjacent to a first end of the plurality of memory cells; a plurality of word lines coupled to the plurality of memory cells of the NAND string; and a first selection line commonly coupled to the at least one pair of first selection transistors of the NAND string.