Provided is a method of performing hybrid automatic repeat request (HARQ) of a receiver in a wireless communication system. The method includes: receiving data in a transmission time interval (TTI) unit consisting of a plurality of consecutive subframes; and transmitting acknowledgment (ACK)/non-acknowledgment (NACK) for the received data, wherein the data is received using a plurality of redundancy versions respectively allocated to the plurality of subframes, and the ACK/NACK is transmitted with an interval of a predetermined processing delay from a transmission time of a specific redundancy version among the plurality of redundancy versions.