The present disclosure relates to the technical field of vehicles, and provides a discharging vehicle and a vehicle charging system. The discharging vehicle includes a discharging control device, a first power battery, a motor, and a motor control circuit. A first electrode and a second electrode of the first power battery are respectively connected to a first input terminal and a second input terminal of the motor control circuit. The discharging control device realizes, by using the motor control circuit, DC step-down charging of the second power battery by the first power battery.