There are provided a method, user equipment, and transmission point device for feeding back channel quality indicator (MU-CQI) to the transmission point in a communication system including the transmission point and a plurality of user equipments, the method comprising steps: the transmission point sending a message to an intended user equipment of the plurality of user equipments; and the intended user equipment calculating the MU-CQI based on the message, and feeding back the MU-CQI to the transmission point. The present disclosure enables dynamic MU operation, and improves link adaptation performance with marginal downlink overhead. And the accuracy is not limited by codebook size.