An electronic device includes a housing, a display exposed through one surface of the housing, at least one ground member, a first battery disposed in the housing and including a first anode and a first cathode, a second battery disposed in the housing and including a second anode and a second cathode electrically connected with the at least one ground member, a charging circuit electrically connected with the first battery and the second battery, a charging interface electrically connected with the charging circuit, and a power management integrated circuit electrically connected with the charging interface and the charging circuit and managing power supplied to the electronic device. When an external power source is connected through the charging interface, the charging circuit connects the first battery and the second battery in series during a first time period and connects the first battery and the second battery in parallel during a second time period.