Abstract: A semiconductor device includes a nitride semiconductor stack having at least two hetero junction bodies where a first nitride semiconductor layer and a second nitride semiconductor layer having a band gap wider than that of the first nitride semiconductor layer are disposed, and includes a drain electrode and, a source electrode disposed to the nitride semiconductor stack, and gate electrodes at a position put between the drain electrode and the source electrode and disposed so as to oppose them respectively in which the drain electrode and the source electrode are disposed over the surface or on the lateral side of the nitride semiconductor stack, and the gate electrode has a first gate electrode disposed in the direction of the depth of the nitride semiconductor stack and a second gate electrode disposed in the direction of the depth of the nitride semiconductor at a depth different from the first gate electrode.