A semiconductor memory device comprises a stack structure including a plurality of layers vertically stacked on a substrate. Each of the plurality of layers includes a first dielectric layer, a semiconductor layer, and a second dielectric layer that are sequentially stacked, and a first conductive line in the second dielectric layer and extending in a first direction. The device also comprises a second conductive line extending vertically through the stack structure, and a capacitor in the stack structure and spaced apart from the second conductive line. The semiconductor layer comprises semiconductor patterns extending in a second direction intersecting the first direction between the first conductive line and the substrate. The second conductive line is between a pair of the semiconductor patterns adjacent to each other in the first direction. An end of each of the semiconductor patterns is electrically connected to a first electrode of the capacitor.