In a discharge system that outputs DC power from a vehicle battery to the outside, improved safety is obtained during discharge of the battery. A discharge system includes an electric car having a battery unit mounted thereon, and a discharge device that discharges the battery unit. The electric car includes a connector to which the discharge device is connected, and a power line that connects the connector and the battery unit to each other. In the power line, switches and switching elements are provided. The switches render the power line conducting upon permission from the discharge device and a battery management unit. The switching elements adjust a current flowing in the power line when the battery unit is discharged.