A semiconductor device includes first and second semiconductor chips, a plurality of leads, a plurality of wires, and a sealing body sealing those components. A first pad electrode, a second pad electrode, and an internal wiring electrically connected to the first and second electrode pads are formed on a main surface of the first semiconductor chip. A third pad electrode of the second semiconductor chip is electrically connected to the first electrode pad of the first semiconductor chip via a first wire, and the second electrode pad of the first semiconductor chip is electrically connected to a first lead via a second wire. A distance between the first lead and the first semiconductor chip is smaller than a distance between the first lead and the second semiconductor chip. The first electrode pad, the second electrode pad and the internal wiring are not connected to any circuit formed in the first semiconductor chip.