A method and device for reporting channel state information in a wireless communication system is disclosed. The method for reporting channel state information (CSI) by means of a terminal in a wireless communication system according to an embodiment of the present invention includes: measuring a first reference signal transmitted from a first subset of antenna ports from among a plurality of antenna ports in a base station; measuring a second reference signal transmitted from a second subset of antenna ports from among the plurality of antenna ports; and reporting the CSI to the base station based on at least one of the measurement of the first reference signal and the measurement of the second reference signal, wherein at least one of the plurality of antenna ports is included in both the first subset and the second subset.