Polarization is the fundamental characteristic of electromagnetic wave as well as time domain and frequency domain.The use of the polarization information can effectively improve radar capabilities of antijamming,target detection and target recongnition.The polarization characteristics of radar antenna are discussed and used to solve some practical problems in radar countermeasures.Based on the decomposition theory of arbitrary polarization wave,the principle of linearly-and-circularly-polarized component method is analyzed.The relevant mathematical models are established.The efffects of axial ratio and polarization mismatch factor on radar receiver sensitivity and Jamming-to-Signal power Ratio at the receiving end are given.The study is of some value in the development of radar counter equipment and the evaluation of radar counter test.