To provide an electronic appliance properly charging an incorporated battery by power supplied from the power source line of a serial bus.

In a case when power is supplied through an AC power source line, a power source controller 20 controls a power source circuit 30 so as to supply power to an appliance main body, the serial bus power source line and the battery without any conditions from this AC power source line. On the other hand, in a case when power is not supplied through the AC power source line and the appliance operates with power supply by the serial bus power source line, the controller 20 decides the power consumption quantity of the appliance main body and the charging power quantity of a battery 30 from the suppliable power quantity of the serial bus power source line reported from a host controller 10 to control the circuit 30. In addition, in a case when power is supplied through neither the AC power source line nor the serial bus power source line, the circuit 30 is drive-controlled to supply the power of the battery 40 for the appliance main body.