The present invention relates to low-heat wireless power receiving device and method for charging a battery with low heat by receiving a wireless power signal from a wireless power transmitting device. When a power receiving coil receives a wireless power signal, a control unit matches impedance by controlling an impedance matching/controlling unit, determines a charging load state of a power receiving unit in accordance with a time-lapse of charging the power receiving unit and a current level detected by a current detecting unit, and selectively turns on a low-heat transforming unit and a high-heat transforming unit in accordance with the selected charging load state, thereby charging the power receiving unit with minimum heat generation.