In a semiconductor integrated circuit device, a first semiconductor chip includes: a buried power rail that supplies first power; and a power line that is provided in a layer above the buried power rail and supplies second power. The buried power rail receives supply of the first power from the back face of the first semiconductor chip via a first through electrode, and the power line receives supply of the second power from the back face of the first semiconductor chip via a second through electrode. The cross-sectional area of the second through electrode is greater than the cross-sectional area of the first through electrode.