Embodies of peripheral a wireless relay system apparatus and method for a multi-path interference removing using by same channel frequency is shown and described, which purpose of the present invention is to overcome extension of service coverage and a dead spot with amplifying same channel frequency, a problem in doing the relay, system wireless relay system was a same frequency interference of RF (Radio Frequency) output is become feedback radiating from tx antenna to rx antenna of the relay system, the wireless relay system apparatus and method effectively eliminates the same frequency interference so that it can ensure an additional system gain and easy to set up relatively to general same frequency relay system.