A method for performing, by a terminal, an uplink HARQ process in a wireless communication system according to one embodiment of the present invention comprises the steps of: transmitting uplink data set to a first HARQ process ID; receiving an ACK/NACK response to the uplink data; and retransmitting the uplink data in response to the ACK/NACK response, wherein when the uplink data includes an SPS signal, the first HARQ process ID is set to one of values #0 to #n−1, and when the uplink data includes a non-SPS signal, the first HARQ process ID is set to one of values #n to #n+m−1, where n is the total number of HARQ processes that can be configured for the SPS signal, and m is the total number of HARQ processes that can be configured for the non-SPS signal.