The present invention relates to a method for performing uplink transmissions by a transmission end in a wireless communication system. In particular, the method includes the steps of: receiving a dynamic uplink grant for a HARQ process from a reception end; and performing an uplink transmission scheduled by the dynamic uplink grant, wherein at least one uplink transmission on at least one configured uplink grant for the HARQ process after receiving the dynamic uplink grant before performing the uplink transmission scheduled by the dynamic uplink grant is skipped.