In this paper, we simulated the earth scene brightness temperature by creating the earth scene data sets and using polarimetric microwave radiative transfer model. On the basis of the fully polarized antenna temperature equation we have derived, the radiometer antenna temperature was also simulated by generating antenna pattern through GRASP9 software. Then by using multiple linear regression method, the M matrix was calculated and the antenna cross-polarization correction for spaceborne polarimetric microwave correlation radiometer was realized. The correction results show that the antenna temperature and earth scene brightness temperature have a linear relationship. Antenna cross-polarization influences the orthogonal channels brightness temperature seriously, especially the vertical polarization brightness temperature. The antenna cross-polarization for each channel has been effectively reduced. Residual cross-polarization is better than -23 dB and the polarization purity is greater than 99.5%. Correction of using M matrix to eliminate the antenna cross-polarization is feasible. It has been proved that this technique is most appropriate for the final correction of antenna cross-polarization for the spaceborne polarimetric microwave correlation radiometer on orbit.