A semiconductor device includes a plurality of active regions including channel regions extending in a first direction on a semiconductor substrate and source/drain regions connected to the channel regions, a plurality of gate electrodes extending in a second direction different from the first direction to intersect the channel regions, a plurality of conductive lines electrically connected to at least one of the source/drain regions and the plurality of gate electrodes through a plurality of vias, and a power line disposed between the semiconductor substrate and the plurality of conductive lines and configured to supply a power supply voltage.