A semiconductor device includes a stacked structure disposed on a substrate. The stacked structure includes a plurality of insulation layers and a plurality of electrode layers alternately stacked in a third direction intersecting with first and second directions. A plurality of channel structures extends through the stacked structure in the third direction. A first wiring group includes a plurality of first horizontal wirings disposed on the stacked structure that are arranged in the first direction and extends in the second direction. A second wiring group includes a plurality of second horizontal wirings disposed on the stacked structure that are arranged in the first direction and extends in the second direction. Each of the plurality of first and second horizontal wirings are connected to corresponding one of the plurality of channel structures. A first line identifier is disposed between the first wiring group and the second wiring group.