A power supply system for an electric powered vehicle, comprising: a main power storage device for storing electric power input/output with respect to an electric motor generating vehicle driving power, a charge device for selectively executing a first power conversion of converting electric power from an external power supply into charging electric power for said main power storage device, and a second power conversion that is at least a portion of power conversion in a direction opposite to the direction of said first power conversion, a sub power storage device having an output voltage lower than the output voltage of said main power storage device, a first power converter, which is connected to a path ( PL1, NL1) between said main power storage device and said electric motor, for converting the electric power from said main power storage device into charging electric power for said sub power storage device, wherein said first power converter has an input electrically connected to the main power storage device and an output electrically connected to the sub power storage device, characterized by a second power converter ( 210; 210#), which is connected to a path ( ACL1, ACL2) between a connection unit for connection with said external power supply and said main power storage device, for converting electric power obtained by said second power conversion through said charge device into the charging electric power for said sub power storage device, wherein said second power converter ( 210; 210#) has an input electrically connected to said charge device and an output electrically connected to said sub power storage device, said second power converter ( 210; 210#) having a rated output smaller than the rated output of said first power converter, and a control device for selectively executing, when said sub power storage device is to be charged, a first charge of charging said sub power storage device by said first power converter while said charge device and said second power converter ( 210; 210#) are stopped, and a second charge of charging said sub power storage device by said charge device and said second power converter ( 210; 210#) while said first power converter is stopped, according to an output state of said sub power storage device, wherein power consumption by said first power converter is greater than a sum of power consumption by said second power converter ( 210; 210#) and power consumption by said charge device through said second power conversion. a main power storage device for storing electric power input/output with respect to an electric motor generating vehicle driving power, a charge device for selectively executing a first power conversion of converting electric power from an external power supply into charging electric power for said main power storage device, and a second power conversion that is at least a portion of power conversion in a direction opposite to the direction of said first power conversion, a sub power storage device having an output voltage lower than the output voltage of said main power storage device, a first power converter, which is connected to a path ( PL1, NL1) between said main power storage device and said electric motor, for converting the electric power from said main power storage device into charging electric power for said sub power storage device, wherein said first power converter has an input electrically connected to the main power storage device and an output electrically connected to the sub power storage device, characterized by a second power converter ( 210; 210#), which is connected to a path ( ACL1, ACL2) between a connection unit for connection with said external power supply and said main power storage device, for converting electric power obtained by said second power conversion through said charge device into the charging electric power for said sub power storage device, wherein said second power converter ( 210; 210#) has an input electrically connected to said charge device and an output electrically connected to said sub power storage device, said second power converter ( 210; 210#) having a rated output smaller than the rated output of said first power converter, and a control device for selectively executing, when said sub power storage device is to be charged, a first charge of charging said sub power storage device by said first power converter while said charge device and said second power converter ( 210; 210#) are stopped, and a second charge of charging said sub power storage device by said charge device and said second power converter ( 210; 210#) while said first power converter is stopped, according to an output state of said sub power storage device, wherein power consumption by said first power converter is greater than a sum of power consumption by said second power converter ( 210; 210#) and power consumption by said charge device through said second power conversion.