<p>The size of a semiconductor device is reduced. A semiconductor chip in which a power MOSFET is placed above a semiconductor chip in which another power MOSFET is formed and they are sealed with an encapsulation resin portion. The semiconductor chips are so arranged that the upper semiconductor chip does not overlap with the area positioned directly above a gate pad electrode of the lower semiconductor chip. The semiconductor chips are identical in size and the respective source pad electrodes and gate pad electrodes of the lower semiconductor chip and the upper semiconductor chip are identical in shape and arrangement. The lower semiconductor chip and the upper semiconductor chip are arranged with their respective centers displaced from each other.</p>