According to one embodiment of the disclosure, a method by which a first device performs SL communication is provided. The method can comprise the steps of: generating, in a MAC CE form, SL CSI related to a channel state between a first device and a second device in a MAC layer; transmitting, to a base station, a first SR triggered on the basis of the SL CSI having the MAC CE form; receiving an SL grant from the base station; and transmitting, to the second device, the SL CSI on an SL resource related to the SL grant.