A vertical structure non-volatile memory device includes semiconductor regions that vertically extend on a substrate, a plurality of memory cell strings that vertically extend on the substrate along sidewalls of the semiconductor regions and include a plurality of memory cells and at least one or more first selection transistors, which are disposed on sides of the memory cells and are adjacent to one another. A plurality of wordlines is connected to the memory cells of the memory cell strings. A first selection line is connected to the selection transistors of the memory cell strings and insulating regions are formed as air gaps between the first selection transistors of the adjacent memory cell strings.