Disclosed herein is a wireless power transfer system. The wireless power transfer system includes a wireless power transmitter receiving power input from the outside to generate a wireless power signal to be transmitted in wireless and transmitting the generated wireless power signal in wireless by a magnetic resonance manner using an LC serial-parallel resonance circuit; a wireless power receiver installed in a charging device to receive the wireless power signal transmitted from the wireless power transmitter by the magnetic resonance manner using the LC serial-parallel resonance circuit and output the received wireless power signal; and a charging circuit installed in the charging device to allow the power output from the wireless power receiver to charge an embedded battery, thereby making it possible to efficiently provide power in wireless.