A method for assembling semiconductor switching elements and a heat sink in a rotary electric machine includes: a first step in which bare chips of the semiconductor switching elements are bonded to the heat sink using a good heat conductive bonding material; a second step which connects the bare chips to a wiring part by wire bonding; and a third step in which a resin which seals the bare chips and the wiring part is applied to the heat sink in a striding manner in a state that output terminal portions of the wiring part and fins of the heat sink are exposed to the outside of the resin.