The present invention provides a method for transmitting or receiving CSI in a wireless communication system and an apparatus therefor. Specifically, a method for reporting CSI by a UE in a wireless communication system may comprise the steps of: receiving CSI-related configuration information from a base station; receiving a reference signal on the basis of the configuration information from the base station; measuring a crosslink interference on the basis of the reference signal; and transmitting CSI including a report about the measured crosslink interference to the base station, wherein the configuration information includes information related to the crosslink interference.