A method for transmitting an uplink control channel from a UE to an eNB in a wireless communication system is disclosed. The method comprises the steps of classifying each of a plurality of resource blocks allocated to a system bandwidth into a plurality of sub-resource blocks; mapping the uplink control channel into a first sub-resource block of a minimum index and a second sub-resource block of a maximum index in accordance with a transmission diversity scheme; and transmitting the uplink control channel to the eNB.