A nonvolatile memory device includes a peripheral circuit including a first active region and a memory block including a second active region on the peripheral circuit. The memory block includes a vertical structure including pairs of a first insulating layer and a first conductive layer, a second insulating layer on the vertical structure, a second conductive layer and a third conductive layer spaced apart from each other on the second insulating layer, first vertical channels and second vertical channels. The second conductive layer and the third conductive layer are connected with a first through via penetrating the vertical structure, the second active region, and a region of the second insulating layer that is exposed between the second conductive layer and the third conductive layer.