Abstract: To improve the robustness of beamforming for polarization array, a general linear combination (GLC) algorithm was applied to the polarization array in this paper. Firstly, analyzing the reason of output signal to interference plus noise ratio decrease with the increase of the number of snapshots under the conditions of sensor disturbance and direction of arrival (DOA) mismatch of the signal of interest (SOI) at high input signal to noise ratio, an improved GLC algorithm was proposed. And then, the input signal to noise ratio was identified by the proposed algorithm according to the size of parameters related to the eigenvalues of the sample covariance matrix (SCM). At high input signal to noise ratio, the GLC algorithm combined with the conversion function was used to calculate the diagonal loading level (DLL). And at a low level of the input signal to noise ratio, the original GLC algorithm was used to calculate the DLL, making the output signal to interference plus noise ratio of the improved GLC algorithm be greater than or equal to that of the original GLC algorithm under any input signal to noise ratio and snapshot. Finally, the effectiveness of the proposed algorithm was verified by simulations under the condition of mainlobe interference.