a method for selecting a relay mode depending on channel status of relay links in a multihop relay broadband wireless communication system and a relay station apparatus for supporting the method . when signals are received from a base station and a mobile station , channel status values of relay links are estimated using the received signals . the estimated channel status values are compared with a preset reference value . according to a result of the comparison , the relay mode for relaying the received signals is selected . accordingly , the reliability of the relayed signal can be enhanced and the capacity of the signal link can be increased .