A charging system is installed outside an electric vehicle to charge an in-vehicle battery mounted in the electric vehicle. The charging system includes a charger that supplies electricity to the in-vehicle battery, an external cooling device that cools the in-vehicle battery, and an off-vehicle controller that controls driving of the charger and the external cooling device. The external cooling device has an external channel which is provided inside the charging system and through which an external refrigerant flows, cooling mechanisms that include at least a compressor and cool the external refrigerant, and a heat exchanger that exchanges heat between the cooled external refrigerant and an internal refrigerant that flows inside the electric vehicle to cool the in-vehicle battery or outside air that is sent to the electric vehicle to cool the in-vehicle battery.