An audio output device is provided. The audio output device includes a battery, a wireless communication circuit, and a control circuit electrically connected to the battery and the wireless communication circuit, wherein the control circuit releases a communication connection with an electronic device using the wireless communication circuit if an electrical connection between the audio output device and a power supply device is sensed, starts charging of the battery of the audio output device by using the power supplied from the power supply device, temporarily activates the wireless communication circuit if either a residual battery quantity of the audio output device or a residual battery quantity of the power supply device satisfies a designated charging condition during charging of the battery of the audio output device, and transmits information about the charging state of the audio output device or the power supply device to the electronic device.