A wireless power transmitting method performed in a wireless power transmitting apparatus includes transmitting a long beacon signal via a transmitting coil; determining whether or not a response signal to the long beacon signal has been received at a wireless communicator; determining whether or not a degree of change in a level of impedance of the transmitting coil is within a reference range responsive to the determination that the response signal is not received; and wirelessly transmitting the power responsive to the determination: that the response signal has been received or that the degree of change is within the reference range.