A method of supporting Hybrid Automatic Repeat Request (HARQ) includes receiving an initial uplink grant on a downlink channel, transmitting uplink data on an uplink channel using the initial uplink grant, receiving a request for retransmission of the uplink data, determining at least one transmission parameter of a channel quality indicator (CQI) from the initial uplink grant, multiplexing retransmission data of the uplink data with the CQI, and transmitting the multiplexed data on the uplink channel. Amount of resources for transmission of the CQI is determined based on the at least one transmission parameter.