The study proposed the polarization array in anti-radiation seeker, which uses joint estimation of polarizational and spatial domains anti-decoy by the differences of the target and decoy. At first, it estimated DOA (direction of angle) and polarimetric parameters of radar and decoys, the DOA supply to guide the ARM and the polarimetric parameters apply to discriminate the radar or decoys, for the purpose of preventing decoy. Then, the all-trajectory simulation on ARM against three point sources bait is accomplished by combining ARM motion equation and guide equation. Many experiments on all-trajectory simulation are done by Monte-Carlo. The simulation results demonstrate the effectiveness on anti-decoy in anti-radiation missile using joint estimation of polarizational and spatial Domains.