VEHICLE POWER SUPPLY SYSTEM

A vehicle power supply system includes a first power line to which a first inverter and a first battery are connected, a second power line to which a second inverter and a second battery are connected, a voltage converter, a charging and discharging control device that operates the inverters and the voltage converter, and a second regenerable electric power acquisition unit that acquires second regenerable electric power. The charging and discharging control device charges the second battery with second regenerative electric power that is power supplied from the second inverter to the second power line during regenerative deceleration, and supplies second surplus regenerative electric power to the first power line in a case where the second regenerative electric power is larger than the second regenerable electric power, wherein the second surplus regenerative electric power is obtained by excluding the second regenerable electric power from the second regenerative electric power.