A method for efficiently manufacturing a semiconductor device, the semiconductor device having an FET and a pn junction diode provided on the same semiconductor substrate, the FET having a Schottky junction for a gate electrode and a gate recess, includes the steps of forming a channel layer, a first etching stopper layer, an n-type common layer, a second etching stopper layer, a p-type layer, and a third etching stopper layer on the semiconductor substrate in that order; etching away the p-type layer and the third etching stopper layer in specific regions; simultaneously forming a source electrode, a drain electrode, a cathode; forming a mask having an opening for forming a gate recess and a gate electrode and an opening for forming an anode; forming the gate recess by etching while the third etching stopper layer prevents the p-type layer from being etched; and simultaneously forming the gate electrode and the anode.