The present invention provides a method and apparatus for performing an uplink Hybrid Automatic Repeat Request (HARQ) operation in an asymmetric multicarrier communication network environment. In one embodiment, a method includes transmitting a HARQ packet to a base station in a transmit time interval of one of a plurality of partitions of an uplink allocation interval on a first carrier by a mobile station. Then, the method includes determining a partition of the uplink allocation interval in which the HARQ packet is transmitted, and determining a HARQ feedback region in the subsequent downlink subframe corresponding to the determined partition. The method further includes receiving HARQ feedback information in the determined HARQ feedback region in the subsequent downlink subframe on a second carrier from the base station.