A vehicle drive system comprises inverters (20, 30) connected electrically with a power supply line (PL2) and a ground line (SL) and controlling the current flowing through each stator coil of each of first and second motor generators (MG1, MG2), and a switch (40) making or breaking the connection between the neutral (N1) of the stator coil of first motor generator (MG1) and a battery (B1). When the first motor generator (MG1) is not used but the second motor generator (MG2) is used, a controller (60) brings the switch (40) into connection state in parallel with voltage conversion operation of a booster unit (10) and controls the inverter (20) to perform voltage conversion operation using the stator coil of first motor generator (MG1) as a reactor.