A contactless power supply system comprising a power transmitter and a power receiver, wherein the power transmitter includes: a high-frequency power generator that generates high-frequency power; at least one power transmitting unit including a transmitting coil and a resonance capacitor connected to the transmitting coil, the power transmitting unit contactlessly transmitting the high-frequency power to the power receiver; at least one power detector that detects reflected power from the power receiver; and a transmitter-side controller for stopping the transmission of the high-frequency power to the power receiver with reference to the reflected power, wherein the power receiver includes: a power receiving unit including a receiving coil magnetically coupled to the transmitting coil and a resonance capacitor connected to the receiving coil, the power receiving unit contactlessly receiving the high-frequency power transmitted from the power transmitting unit; a rectifier circuit that converts the high-frequency power received by the power receiving unit into direct current power; a power storage device chargeable with the direct current power; a switch operated to electrically connect and disconnect a path to supply the direct current power to the power storage device; and a receiver-side controller that operates the switch so as to electrically disconnect the path when the power storage device is in a full charge state, characterised in that the transmitter-side controller is configured to stop the transmission of the high-frequency power in response to a determination that the power storage device is completely charged based upon the reflected power reaching or exceeding a power-stop threshold. a high-frequency power generator that generates high-frequency power; at least one power transmitting unit including a transmitting coil and a resonance capacitor connected to the transmitting coil, the power transmitting unit contactlessly transmitting the high-frequency power to the power receiver; at least one power detector that detects reflected power from the power receiver; and a transmitter-side controller for stopping the transmission of the high-frequency power to the power receiver with reference to the reflected power, a power receiving unit including a receiving coil magnetically coupled to the transmitting coil and a resonance capacitor connected to the receiving coil, the power receiving unit contactlessly receiving the high-frequency power transmitted from the power transmitting unit; a rectifier circuit that converts the high-frequency power received by the power receiving unit into direct current power; a power storage device chargeable with the direct current power; a switch operated to electrically connect and disconnect a path to supply the direct current power to the power storage device; and a receiver-side controller that operates the switch so as to electrically disconnect the path when the power storage device is in a full charge state, characterised in that the transmitter-side controller is configured to stop the transmission of the high-frequency power in response to a determination that the power storage device is completely charged based upon the reflected power reaching or exceeding a power-stop threshold.