The application relates to a method for transmitting and receiving, by a station, signals in a wireless LAN system and, more specifically, to a method for, when a station in a wireless LAN system is assigned one or more channels which do not include a primary channel on the system, setting and updating a network allocation vector (NAV) value applied to the one or more allocated channels, a method for transmitting and receiving signals on the basis of the same, and an apparatus therefor.