Disclosed are a method for performing uplink transmission in a wireless communication system and an apparatus therefor.Specifically, a method for performing uplink transmission in a wireless communication system, which is performed by a user equipment includes: receiving, from a base station, configuration information for performing uplink transmission without an uplink grant; and transmitting uplink data, to the base station, through at least one uplink resource configured based on the configuration information, in which the configuration information may be received through a higher layer signaling, and the configuration information may include information related to repetition transmission of the uplink data.