The present invention provides a method for scheduling a SDMA user group in an MU MIMO system and a base station. The method comprise the following steps: calculating, according to channel state information, a projection matrix of a channel matrix of each user in a user group on a joint channel matrix of other users in the same user group, where the user group is selected from a plurality of users; calculating a capacity metric of the user group according to the projection matrixes; and selecting an optimal user group according to the metrics of a plurality of user groups. The present invention effectively eliminates the MUI on terminal users at the transmitter side, and reduces the computational complexity.