A semiconductor device includes a substrate including a memory cell region and a logic region; a variable resistance memory device on the memory cell region; a logic device on the logic region; a first horizontal bit line extending in a horizontal direction on a surface of the substrate on the memory cell region and electrically connected to the variable resistance memory device; a second horizontal bit line extending in a horizontal direction on the surface of the substrate on the logic region and electrically connected to the logic device; and a vertical bit line electrically connected to the first horizontal bit line and the second horizontal bit line and extending perpendicular to the surface of the substrate.