A method and an apparatus for transmitting/receiving a downlink signal in a wireless communication system are provided. Carrier information about a second carrier that is different from a first carrier can be transmitted on the first carrier. Downlink data for UE can be transmitted on the second carrier based on the carrier information. The first carrier is a carrier having a synchronisation signal and a physical broadcast channel, and the second carrier can be a carrier without any synchronisation signals or physical broadcast channels. The first carrier can be operated on a single resource block in a guard frequency that is used in the wireless communication system.