Abstract: As radar applications continue to extend and detection scenarios become increasingly complicated, there is an urgent need for superior resolution capability. Research shows that the amplitude ratio and phase difference of the target will affect the radar resolution effect. The relative amplitude-phase relationship of targets and the coherent superposition effect can be changed by different transmitting-receiving polarizations. The fully utilization of polarization information can enhance the spatial resolution of the radar. However, the polarization characteristics of targets are various. There is a lack of theoretical tools to quantitatively characterize the differences in polarization characteristics, which makes it difficult to analyze the increase of radar resolvability with polarization information. To analyze the effect of target polarization characteristic difference on radar resolution effect, this paper firstly explores a quantitative characterization method of resolution effect for radar target echo and gives the mathematical definition for the degree of resolvability of dual-target echo. Then, the concept of divisibility factor in the polarization domain is proposed to describe the effect of target polarization characteristic difference on radar resolution effect. Finally, numerical simulations and chamber measurements are carried out for typical scattering structures. The analysis provides theoretical foundation for optimal polarization selection. The study shows that the larger the difference in target polarization characteristics is, the easier it is to change the transmitting-receiving polarizations to improve the resolution effect.