A method and apparatus for determining to be a relay UE in a wireless communication system. A user equipment (UE) receives reference signal received power (RSRP) based criteria from a network, and determines to be a relay UE when a specific condition corresponding to the RSRP based criteria is met. The UE may further receive a hysteresis value from the network. When a measured RSRP of the UE plus the hysteresis value is below the RSRP threshold, the UE may determine to be a relay UE.