A method by which a terminal measures channel state information (CSI) in an unlicensed band is disclosed. Particularly, the method comprises: receiving at least one channel state information-reference signal (CSI-RS) through at least one listen before talk (LBT) sub-band of a plurality of LBT sub-bands for transmitting a plurality of CSI-RSs within one transmit opportunity (TxOP) section; determining each measurement use for at least one CSI-RS; and measuring the CSI on the basis of each measurement use for the at least one determined CSI-RS, wherein the determination of each measurement use for the at least one CSI-RS is the determining of whether the CSI-RS is for an interference measurement or the CSI-RS is for a signal measurement.