A method for transmitting and receiving data in a communication system

A method and an apparatus for transmitting/receiving data in a communication system are provided to obtain user multiplexing effect by allowing a multicast or single user to use extra power. A terminal requests joining from a base station providing a multicast service, and joins a corresponding multicast group after authentication. When the terminal successfully receives a certain number of frames continuously, it transmits a flag bit to the base station(410) because there is a high probability that there is a user who has a channel gain worse than that of the terminal, and transitions to a non-feedback state(415). If the number of successful receptions of frames is smaller than the certain number, the terminal remains in a feedback state and feeds back its CQI(Channel Quality Indication) to the base station.