A vehicular power transmitting system including an oil pump constructed to sufficiently reduce a required drive torque. A high-pressure-port discharge amount of first and second high-pressure passages of the oil pump is determined such that an amount of consumption of working oil of relatively high pressure can be afforded only by the high-pressure-port discharge amount, during steady-state running of a vehicle in which engine speed is not lower than a predetermined threshold value corresponding to a predetermined lowest target input shaft speed of a continuously variable transmission for its shifting control. The pressure of the working oil discharged from first and second low-pressure discharge passages is kept at a predetermined low level, and the required drive torque of the oil pump is sufficiently reduced.