With the rapid development of high resolution earth observation satellite, the contradiction between data rate and system bandwidth ground receiving system facing the increasingly prominent, single polarization inherent reception is difficult to meet the bandwidth requirements, while receiving polarization multiplexing can effectively solve the problem of insufficient bandwidth. But the difficulty lies in the existence of polarization multiplexing inevitable interference two polarization, polarization isolation requirements of satellite ground link is very high. The theoretical analysis shows that the polarization multiplexing receiver performance depends on the combination between satellite and ground isolation, with satellite antenna spatial relationship is different, the isolation will change. Due to the uncertainty of satellite ground isolation design, polarization multiplexing receiving ratio standard is the main difficulty of polarization multiplexing receiving results processing, for verification of the theoretical analysis, an experiment system of polarization multiplexing receiver.