An inverter apparatus is composed of an insulated metal substrate, a conductive stud, a printed circuit board, a conductive spacer, and a bus bar. An inverter output stage is mounted on the insulated metal substrate. The conductive stud is coupled to a main surface of the insulated metal substrate, and electrically connected with the inverter output stage. The printed circuit board is supported by the stud. The stud is coupled on the rear surface of the printed circuit board. Provided on the main surface of the printed circuit board is a circuit connected to the inverter output stage. The conductive spacer is coupled on the main surface of the printed circuit board, and electrically connected with the stud. The bus bar is coupled to the spacer.