A PCU (20) comprises an anchoring pedestal (22) that is attached to the opening of a transaxle and that has been molded from resin so as to be formed integrally with a terminal block (21); a cooler (27) that is disposed on top of the anchoring pedestal (22) and that has a power module; a heat-conductive board stay (14) connected to the top of the cooler (27); and a control board (29) connected to the top of the board stay (14). This mounting structure is configured such that by disposing the board stay (14) near a cooling tube (17a) for introducing coolant cooled by a radiator and by attaching the stay to the cooler (27) via a heat-dissipating sheet (61a) for actively conducting heat from the control board, the control board (29) is cooled by the coolant before the coolant has absorbed heat. Thus, the pressure elevation converter and inverter that form the power control unit and the motor are housed as a single component inside one case and the coolability of the control board disposed at the top of the power control unit can be ensured.