A method and apparatus for dynamically allocating and releasing a Channel Quality Information CHannel (CQICH) to and from a Mobile Station (MS) in a Base Station (BS) communicating with a plurality of MSs on a common radio channel in a wireless communication system are provided, in which the BS determines whether the MS is under a first group, when a CQICH is to be allocated to the MS, determines whether any data transmission has occurred for a CQICH allocation period preset for the first group and counted from a reallocation time, if the MS is under the first group, and groups the MS to a second group and reallocates a CQICH to the MS, the second group having a lower priority level than the first group, if no data transmission has occurred for the CQICH allocation period.