A method and apparatus are described for transmitting a reference signal in a multi-antenna system. A terminal generates a plurality of reference signal sequences to which cyclic shift values different from each other are allocated, generates an orthogonal frequency division multiplexing (OFDM) symbol to which the plurality of reference signal sequences are mapped, and transmits the OFDM symbol to a base station through a plurality of antennas. The respective cyclic shift values allocated to the respective reference signal sequences are determined on the basis of a parameter n indicated by a cyclic shift field transmitted from a physical downlink control channel (PDCCH).