A semiconductor device includes a first gate electrode, a plurality of first source electrodes, a second gate electrode, and a plurality of second source electrodes. The first gate electrode is arranged with no other electrode between the first gate electrode and a first short side of the semiconductor substrate. The plurality of first source electrodes include a plurality of approximately rectangular first source electrodes arranged in stripes extending parallel to the lengthwise direction of the semiconductor substrate. The second gate electrode is arranged with no other electrode between the second gate electrode and a second short side of the semiconductor substrate. The plurality of second source electrodes include a plurality of approximately rectangular second source electrodes arranged in stripes extending parallel to the lengthwise direction of the semiconductor substrate.