Provided is a semiconductor memory device. The semiconductor memory device includes a peripheral circuit gate pattern on a first substrate, an impurity region in the first substrate and spaced apart from the peripheral circuit gate pattern, a cell array structure on the peripheral circuit gate pattern, a second substrate between the peripheral circuit gate pattern and the cell array structure, and a via that is in contact with the impurity region and disposed between the first substrate and the second substrate. The via electrically connects the first and second substrates to each other.