An electronic apparatus is provided. The electronic apparatus includes: a main circuit; and a power supply circuit configured to receive external power from an external power supply and supply operating power to the main circuit. The power supply circuit includes: a converter; and a lightning protection circuit that includes: a varistor configured to have a first rated voltage corresponding to a breakdown voltage of a device of the converter; and a surge arrester connected in series to the varistor and configured to have a second rated voltage, and based on the external power being higher than the first rated voltage of the varistor, the varistor is clamped so that a voltage applied to the converter does not exceed the first rated voltage, and based on a voltage applied to the surge arrester being equal to or higher than the second rated voltage, the surge arrester is short-circuited.