Disclosed are a relay method and device in a communication system. An operation method of a first communication node comprises the steps of: transmitting a reference signal to one or more candidate R nodes; receiving first feedback information including a minimum value of a first RSRP from a first candidate R node belonging to the one or more candidate R nodes; receiving second feedback information including a minimum value of a second RSRP from a second candidate R node belonging to the one or more candidate R nodes; comparing a first value based on the first feedback information with a second value based on the second feedback information; when the first value is greater than the second value, selecting the first candidate R node as an R node that is to perform a relaying operation; and communicating with a second communication node via the R node.