A vehicle drive system comprises inverters connected electrically with a power supply line and a ground line and controlling the current flowing through each stator coil of each of first and second motor generators, and a switch making or breaking the connection between the neutral of the stator coil of first motor generator and a battery. When the first motor generator is not used but the second motor generator is used, a controller brings the switch into connection state in parallel with voltage conversion operation of a booster unit and controls the inverter to perform voltage conversion operation using the stator coil of first motor generator as a reactor.