A semiconductor device according to an embodiment includes a nitride semiconductor layer, a plurality of source electrodes provided on the nitride semiconductor layer, a plurality of drain electrodes, a plurality of gate electrodes, a first interconnection having a first distance from the nitride semiconductor layer and electrically connecting the source electrodes, a second interconnection electrically connecting the gate electrodes, and a third interconnection having a third distance from the nitride semiconductor layer and electrically connecting the drain electrodes. Each of the drain electrodes are provided between the source electrodes. Each of the gate electrodes are provided between each of the source electrodes and each of the drain electrodes. The third distance is larger than the first distance.