A noncontact charger system comprising: a charger which has a power transmitting unit including a power transmitting planar coil that transmits high-frequency charging power; and a charged device which has a power receiving unit including a power receiving planar coil which is magnetically coupled to the power transmitting planar coil to receive the high-frequency charging power in a state in which the power receiving planar coil opposes the power transmitting planar coil to form a predetermined gap; and a control unit, characterised in that the charger further has a high-frequency authenticating power generating unit including a primary authentication planar coil, the high-frequency authenticating power generating unit generates high-frequency authenticating power for authenticating the charged device, the primary authentication planar coil transmits the high-frequency authenticating power to the charged device and receives a high-frequency authenticating signal for authenticating the charged device, the charged device further has a high-frequency authenticating signal generating unit including a secondary authentication planar coil which is magnetically coupled to the primary authentication planar coil to receive the high-frequency authenticating power, the high-frequency authenticating signal generating unit further includes a power circuit which generates drive power for generating the high-frequency authenticating signal from the high-frequency authenticating power, the secondary authentication planar coil outputs the high-frequency authenticating signal to the primary authentication planar coil, the control unit is configured to detect a presence of a foreign object in the gap by detecting a change in an amplitude of a voltage value at the primary authentication planar coil, and a space between the power transmitting planar coil and the power receiving planar coil overlaps with a space between the primary authentication planar coil and the secondary authentication planar coil. a charger which has a power transmitting unit including a power transmitting planar coil that transmits high-frequency charging power; and a charged device which has a power receiving unit including a power receiving planar coil which is magnetically coupled to the power transmitting planar coil to receive the high-frequency charging power in a state in which the power receiving planar coil opposes the power transmitting planar coil to form a predetermined gap; and a control unit, characterised in that the charger further has a high-frequency authenticating power generating unit including a primary authentication planar coil, the high-frequency authenticating power generating unit generates high-frequency authenticating power for authenticating the charged device, the primary authentication planar coil transmits the high-frequency authenticating power to the charged device and receives a high-frequency authenticating signal for authenticating the charged device, the charged device further has a high-frequency authenticating signal generating unit including a secondary authentication planar coil which is magnetically coupled to the primary authentication planar coil to receive the high-frequency authenticating power, the high-frequency authenticating signal generating unit further includes a power circuit which generates drive power for generating the high-frequency authenticating signal from the high-frequency authenticating power, the secondary authentication planar coil outputs the high-frequency authenticating signal to the primary authentication planar coil, the control unit is configured to detect a presence of a foreign object in the gap by detecting a change in an amplitude of a voltage value at the primary authentication planar coil, and a space between the power transmitting planar coil and the power receiving planar coil overlaps with a space between the primary authentication planar coil and the secondary authentication planar coil.