A battery charging system includes a battery, a load and a controller to control supply power to be supplied from an external power source to the battery and the load, in accordance with a request charging power and a request load power. The controller limits power supplied from the external power source to the battery to an allowable battery power, and distributes the supply power from the external power source between the battery and the load in a state holding limitation of limiting the supply power from the external power source to the allowable battery power when a request for the supply of power to the load is generated.