Apparatus and method for retransmission request in wireless communication system using relay

An apparatus and a method for re-transmitting data in a wireless communication system using a relay system are provided to improve reliability on data by making a relay station re-transmit only non-error data to a base station. A method for re-transmitting data in a wireless communication system using a relay system includes the steps of: if an uplink signal of a terminal is received from a relay station, acknowledging the signal received from the relay station(221); if data is received from the relay station, checking whether an error exists within the data(223); if the data is erroneous, requesting re-transmission of the data to the relay station(225). The method further includes the steps of: transmitting scheduling information for the uplink signal of the terminal to the relay station or the terminal; comparing a signal reception success rate from the terminal with a signal reception success rate of the relay station to determine a node which will receive the uplink signal; and if the signal reception success rate from the relay station is higher than the signal reception success rate from the terminal, determining the relay station as the node which will receive the uplink signal.