A method for reporting channel state for an unlicensed band in a wireless communication system, according to an embodiment of the present invention, is performed by a terminal, and may comprises the steps of: blind-detecting a reference signal in an unlicensed band cell (UCell) subframe according to the setting of a plurality of channel state reports; determining, according to the blind detection result, whether or not the UCell subframe is an available resource for the channel state reports; and if the UCell subframe is determined to be an available resource for the channel state reports, calculating a value for the channel state reports using the reference signal detected in the UCell subframe.