A method for reporting a channel status in a mobile communication system including a relay station (RS) is provided. When a mobile terminal in the coverage of a base station (BS) receives a service through an RS, the RS reports a channel status between the RS and the terminal to the BS to allow the BS to decide whether or not to communicate with the terminal through the RS. In the method, a first RS in communication with a BS and at least one terminal measures a channel quality with a first terminal and compares the measured channel quality with a threshold and transmits a report message to the BS according to the comparison. The report message is to request the BS to measure a channel quality of at least one of a second RS and the first terminal in communication with the BS.