A method for transmitting Channel Quality Indicators (CQIs) of all carrier bands in a system using a plurality of carrier bands (legacy system bands) is disclosed. In order to provide sufficient information to a scheduler, the CQIs of all the carrier bands are generated and transmitted by the same method or a predetermined number of carrier bands are selected and only the CQIs of the selected carrier bands are transmitted. Thus, it is possible to efficiently control signal resources. By simply expanding the method for transmitting the CQIs of the carrier bands, it is possible to facilitate the expansion of the system.