According to certain embodiments, a power transmission device comprises an induction circuit configured to transmit a wireless power signal through a charging pad and receive a signal from an external device; and at least one processor operatively connected to the induction circuit, wherein the processor is configured to: enter a wireless charging protection mode for wireless charging of the external device, measure a current value of the wireless power signal, and release the wireless charging protection mode when the packet information is not included in the signal transmitted from the external device and the measured current value or variation of the current value exceeds a threshold value.