A semiconductor device is composed of a pair of semiconductor chips (402, 404) arranged parallel on the same flat plane; a high voltage bus bar (21) bonded on the surface on the collector side of one semiconductor chip (402); a low voltage bus bar (23) connected to the surface on the emitter side of the other semiconductor chip (404) with a bonding wire (27); a first metal wiring board (24-1) connected to the surface on the emitter side of the semiconductor chip (402) with a bonding wire (26); a second metal wiring board (24-2) bonded on the surface on the collector side of the semiconductor chip (404); a third metal wiring board (24-3) connected to the first metal wiring board (24-1); a fourth metal wiring board (24-4) connected by being bent from an end portion of the second metal wiring board (24-2); and an output bus bar (24) having output terminals (405) extending from each end portion of the third metal wiring board (24-3) and that of the fourth metal wiring board (24-4).