An apparatus and method for removing interference in a transmitting end of a multi-antenna system is provided. The method includes decomposing a channel matrix including channel coefficients for a plurality of terminals, calculating a value proportional to an interference signal for each of antennas, and calculating a sum of a transmission signal and the calculated value for each terminal and multiplying the calculated sum by the decomposed channel matrix. Accordingly, channel capacity can be improved by optimizing a data transfer rate and transmission power for each terminal.