The present invention relates to a wireless communication system. More particularly, the present invention relates to a method and to an apparatus for transmitting an SRS in a multi-antenna system. The method comprises the steps of: acquiring specific information for discriminating a first antenna group and a second antenna group from among a plurality of antennas, wherein said first antenna group includes one or more antennas which are set to a turned-on state to perform communication with a base station, and said second antenna group includes one or more other antennas which are set to a turned-off state; transmitting an SRS to the base station if a predetermined condition is satisfied, under the condition that the second antenna group is set to the turned-off state; and setting the second antenna group to a turned-off state after the transmission of the SRS.