A method for realizing space division multiplexing is provided. The method comprises steps as follows: A. acquiring space information of users, and calculating space division isolation between the users based on the acquired space information; B. generating a set of user groups for the space division multiplexing based on the space division isolation between users calculated in step A; C. selecting a user group from the set of user groups for the space division multiplexing generated in step B and allocating the same physical resource to two users among the selected user group when conducting the space division multiplexing. An apparatus for realizing space division multiplexing is further provided. Using said method and apparatus, the space division isolation can be realized reasonably with accuracy.