The present invention relates to a transmission interference cancellation method for a multiuser MIMO system. The method includes decomposing a channel matrix to represent formulae of permutation matrixes including a first matrix and a second matrix; determining an optimal permutation matrix among a plurality of available permutation matrixes using a norm of multiplication of the second matrix and a transmitting data vector; and determining the second matrix using the determined optimal permutation matrix and calculating a transmitting precoding vector using the determined second matrix and the transmitting data vector.