Disclosed in the present application is a method by which a terminal reports aperiodic channel status information (CSI) to a base station in a wireless communication system. Particularly, the method comprises the steps of: receiving, from the base station, through downlink control information (DCI), a CSI report triggering message including information on at least one CSI process among a plurality of CSI processes and on one aperiodic reference signal among a plurality of aperiodic reference signal resources included in the at least one CSI process; and updating the aperiodic CSI relating to the at least one CSI process and reporting the same to the base station, on the basis of the one aperiodic reference signal.