Abstract: In this paper, an improved rank-reduction algorithm based on Householder Multi-stage Weiner Filter (Householder-MWF) is proposed for the application of space-time anti-jam in GPS receivers. The new algorithm retains the forward decomposition process of the original algorithm and improves its backward recursion by utilizing the decomposition property of Multi-stage Weiner Filtering (MWF), so obtains an order-recursive implementation structure and greatly promotes the real-time performance. Its shown that the computation complexity of the proposed algorithm is almost the same as the original algorithm and is apparently lower than algorithms based on the Correlation Subtraction Structure (CSS) MWF. The anti-jam performance of the proposed algorithm is verified by simulations.