An apparatus and method for supporting relaying in a wireless communication system are provided. The apparatus and method include a transmitting apparatus which acquires channel information between the transmitting apparatus and an RS, pre-encodes a transmission signal to be transmitted to the RS with the channel information, transmits the pre-coded signal to the RS, and acquires, upon receipt of a signal from the RS, a signal transmitted by a receiving apparatus by eliminating the transmission signal transmitted to the RS from the received signal. Accordingly, the apparatus and method improve system capacity gain without adding time resources.