Provided is a method for transmitting a sidelink message by a terminal in a wireless communication system. The method comprises: selecting at least one sidelink message among a plurality of sidelink messages, on the basis of the importance of each of the sidelink messages; selecting at least one carrier among a plurality of predetermined carriers, on the basis of the priority of each of the carriers and the importance of the selected at least one sidelink message; and transmitting the selected at least one sidelink message through the selected at least one carrier, wherein a sidelink message having relatively high importance among the selected at least one sidelink message is preferentially transmitted through a carrier having relatively high priority among the selected at least one carrier.