Abstract: A novel algorithm to estimate the direction of arrivial(DOA)weak signal while restraining intensive coherent interferences is presented on the basis of uniform linear array. The accurate numbers and DOAs of the interferences, divide the antenna array into two equalsize virtual subarrays, make use of the reference direction of the desired signals, use subarray beamforming to form a signal whose phase relative to the desired signal is a function of the DOA, and employ the phase comparison method to obtain the DOA of weak signal. Estimating angle of direction and beamforming are iteratively performed to get the accuracy angle estimation for weak signals. The approach improves the array ability to suppress the coherent interferences, and shows high estimation accuracy. Both the theoretical analysis and the simulation results verify the validity and feasibility of the proposed method.