A semiconductor memory device includes; a first impurity region and a second impurity region spaced apart in a semiconductor substrate, a bit line electrically connected to the first impurity region, a storage node contact electrically connected to the second impurity region, an air gap between the bit line and the storage node contact, a landing pad electrically connected to the storage node contact, a buried dielectric pattern on a sidewall of the landing pad and on the air gap, and a spacer capping pattern between the buried dielectric pattern and the air gap.