Abstract: To achieve DOA estimation in the background of strong interferences, there was a novel methodology based on using the technology of adaptive nulling antenna. In the new methodology, the weight vector was obtained by LMS algorithm and power inversion standard firstly as what the nulling antenna did. Then the reciprocal of the antenna pattern was defined as the special spectrum, whose peak value was corresponding to the estimated DOA. Through observation of spectrum and data analysis of step sizes and SNRs in algorithm, the results showed that it could achieve DOA estimation, what’s more, the estimated error would be smaller when the step size was shorter and the SNR was larger.Compared with the existing MUSIC spectrum estimation method, the new strategy has less compute load, since it does not need to do the estimation for the number of signal and eigenvalue decomposition of covariance matrix.