Method for performing asynchronous harq operation and device therefor

A method for performing an asynchronous HARQ operation by a terminal in a wireless communication system may comprise the steps of: receiving, in a first subframe, control information indicating a first subframe offset value between a subframe in which downlink data has been received from a base station and a subframe in which a downlink HARQ feedback for the downlink data is received; receiving the downlink data in the first subframe from the base station; and when a subframe allowing only downlink transmission or reception is present between the subframe in which the downlink data has been received and the subframe in which the downlink HARQ feedback has been transmitted, transmitting the downlink HARQ feedback for the downlink data in a second subframe that is subsequent to the first subframe by the predetermined number of subframes, wherein the predetermined number of subframes corresponds to a subframe offset value calculated by adding the first subframe offset value and a second subframe offset value that is previously defined for a case where the subframe allowing only the downlink transmission or reception is present.