An oil discharge structure of a baffle plate for discharging oil from a space of a gear side to a space of a transmission side with a space-saving design is provided. A slit is formed in a side face plate facing a final gear of a case side baffle plate to discharge the oil from an oil volume X in the circumference of the final gear to an oil volume Y stored in a clearance between the case side baffle plate and the transmission case, and in a clearance between the housing side baffle plate and the housing. This provides a compact structure that is not larger in a radial direction of the final gear and discharges the oil in the oil volume X.