A power control unit which comprises a plurality of semiconductor elements including a plurality of high-potential side semiconductor elements and a plurality of low-potential side semiconductor elements, and each having a first face and a second face, a collector terminal or an emitter terminal provided on the first face, or an emitter terminal and a gate terminal provided on the first face; a plurality of bus bars electrically connected with at least one of the semiconductor elements, and forming a power module together with the semiconductor elements; a terminal block having signal lines and a resin mold which supports the signal lines; and an engaging portion provided on at least one of the bus bars, and engaging with a portion of the terminal block, and also supporting the terminal block, the signal lines directly connected with the gate electrodes through the engaging portion.