To provide an inverter unit with excellent manufacturing performance and with current carrying capacity increased and size reduced by further increasing the cooling efficiency of a power efficiency device. The inverter unit includes: a semiconductor chip constituting an arm of an inverter; a first conductor 33 joined to a positive side of the semiconductor chip; and a second conductor 35 joined to a negative side of the semiconductor chip. The first and second conductors are disposed above a cooler 22 cooling the semiconductor chip so that a joint surface of the first conductor 33 which is joined to a positive electrode of the semiconductor chip and a joint surface of the second conductor 35 which is joined to a negative electrode of the semiconductor chip are not in parallel to a surface of the cooler 22.
