A wireless power receiver which is configured to wirelessly receive power from a wireless power transmitter and transfer the power to a load, the wireless power receiver comprising: a reception unit configured to receive power from the wireless power transmitter by using a resonance scheme; a rectifying unit connected to the reception unit in order to rectify the received power; a load management unit connected between the rectifying unit and the load to control an impedance of the load according to a charged state of the load; wherein the power transmitted from the wireless power transmitter is controlled by the controlled impedance, wherein the load includes, a battery cell configured to receive the power from the wireless power receiver and to drive an electronic appliance, a first switch device configured to open or short so that the power supplying to the battery cell is maintained or blocked, a charging control unit configured to identify a charged state of the battery cell and controlling the first switch device according to the charged state of the battery cell,wherein the charged state of the load is the charged state of the battery cell, wherein the load management unit includes: a second switch device different from the first switch device and connected in parallel to a smoothing capacitor of the rectifying unit; a current detecting unit connected between the rectifying unit and the load to detect a current flowing through the load; and a control unit configured to control the second switch device based on to the detected current by the current detecting unit when the first switch device of the load has open state or short state according to the charged state of the battery cell wherein the second switch device is oppositely operated to the first switch device. a reception unit configured to receive power from the wireless power transmitter by using a resonance scheme; a rectifying unit connected to the reception unit in order to rectify the received power; a load management unit connected between the rectifying unit and the load to control an impedance of the load according to a charged state of the load; wherein the power transmitted from the wireless power transmitter is controlled by the controlled impedance, wherein the load includes, a battery cell configured to receive the power from the wireless power receiver and to drive an electronic appliance, a first switch device configured to open or short so that the power supplying to the battery cell is maintained or blocked, a battery cell configured to receive the power from the wireless power receiver and to drive an electronic appliance, a first switch device configured to open or short so that the power supplying to the battery cell is maintained or blocked, a charging control unit configured to identify a charged state of the battery cell and controlling the first switch device according to the charged state of the battery cell,wherein the charged state of the load is the charged state of the battery cell, wherein the load management unit includes: a second switch device different from the first switch device and connected in parallel to a smoothing capacitor of the rectifying unit; a current detecting unit connected between the rectifying unit and the load to detect a current flowing through the load; and a control unit configured to control the second switch device based on to the detected current by the current detecting unit when the first switch device of the load has open state or short state according to the charged state of the battery cell wherein the second switch device is oppositely operated to the first switch device. a second switch device different from the first switch device and connected in parallel to a smoothing capacitor of the rectifying unit; a current detecting unit connected between the rectifying unit and the load to detect a current flowing through the load; and a control unit configured to control the second switch device based on to the detected current by the current detecting unit when the first switch device of the load has open state or short state according to the charged state of the battery cell wherein the second switch device is oppositely operated to the first switch device.