An apparatus and a method for multi-user scheduling in a MIMO system are disclosed. In an embodiment the method includes, receiving, by a base station, PMIs and CQIs of first codewords and second codewords, where the PMIs and the CQIs are fed back by N UEs; grouping UEs whose PMIs are the same into one pairing group to divide the N UEs into M pairing groups; and determining a user pairing combination of each pairing group according to a CQI of a first codeword of each UE in the pairing group and a CQI of a second codeword of each UE in the pairing group. The method further includes determining an optimal user pairing combination from M user pairing combinations. The base station schedules two UEs in the optimal user pairing combination simultaneously.