A semiconductor memory device includes a stack including a plurality of layers vertically stacked on a substrate, each of the layers including a bit line extending in a first direction and a semiconductor pattern extending from the bit line in a second direction crossing the first direction, a gate electrode along each of the semiconductor patterns stacked, a vertical insulating layer on the gate electrode, a stopper layer, and a data storing element electrically connected to each of the semiconductor patterns. The data storing element includes a first electrode electrically connected to each of the semiconductor patterns, a second electrode on the first electrode, and a dielectric layer between the first and second electrodes. The stopper layer is between the vertical insulating layer and the second electrode.