A semiconductor device includes a substrate having an active region; a bit line structure on the substrate and extending in one direction; a bit line contact electrically connecting a first impurity region of the active region and the bit line structure; and a storage node contact disposed on a sidewall of the bit line structure and electrically connected to a second impurity region of the active region, wherein the storage node contact includes a vertical extension portion extending in a vertical direction, perpendicular to an upper surface of the substrate, and a horizontal extension portion integrally connected to the vertical extension portion and extending in a horizontal direction, parallel to the upper surface of the substrate.