the present document related to a method and apparatus for transceiving a signal capable of verifying the validity of an available channel in a wireless communication system . according to the present invention , a scheme for transceiving available channel information , a scheme for requesting / responding to a channel validity inquiry , and a scheme for transceiving a contact verification signal are provided , and accordingly , a scheme for supporting the accurate and efficient operation of an unlicensed device while protecting a licensed device in a whitespace band is provided .