An object of the present invention is to provide an electronic device capable of receiving payment of a charge required for a charging process even though a secondary battery of the electronic device ran into an overdischarge state and also extricating itself from the overdischarge state, and a charger used for the same. A charger (3) executes a power transmission before it conducts a proximity noncontact communication with an electronic device (2), continues this power transmission until a preliminary charging stop notification signal is sent from the electronic device (2), and conducts the proximity noncontact communication regarding to a billing process with the electronic device (2) when the preliminary charging stop notification signal is sent. After the communication regarding to the billing process is ended, the charger (3) gives a charge of electricity to the electronic device (2) again. The electronic device (2) charges a secondary battery (28) by using the power transmission, then executes the charging up to a level at which the proximity noncontact communication regarding to the billing process can be conducted, then conducts the proximity noncontact communication regarding to the billing process with the charger (3), and then restarts the power transmission from the charger (3) to execute the charging until the secondary battery (28) is fully charged. In this manner, the noncontact charging and the proximity noncontact communication are executed between the electronic device (2) and the charger (3) in a time-division system.