A memory device includes a substrate defined with a first cell region and a second cell region, and a row decoder region between the first and second cell regions; a peripheral circuit defined in the first and second cell regions of the substrate; pass transistors defined in the row decoder region of the substrate; bottom wiring layers disposed in a first dielectric layer covering the peripheral circuit and the pass transistors; a memory cell array defined on the first dielectric layer; a second dielectric layer defined on the first dielectric layer, and covering the memory cell array; top wiring layers disposed in a third dielectric layer defined on the second dielectric layer; and global lines disposed in the row decoder region, and configured to transfer operating voltages to the pass transistors, wherein the global lines are disposed only in at least one bottom wiring layer from among the bottom and top wiring layers.