Herein, the scattering characteristics of GF-3 full-polarization SAR (synthetic aperture radar) images were evaluated based on H/A/α polarization decomposition method, and the polarization characteristics of typical ground features in GF-3 and RADARSAT-2 full-polarization SAR images were analyzed. Evaluation method of polarization measurement accuracy based on traditional H/α characteristic scattering plane and improved intra-class aggregation and inter-class dispersion were proposed. Results show that the polarization scattering characteristics of GF-3 full-polarization SAR are clearly for different types of surface features. The average deviations of scattering entropy and scattering angle of three types of surface features are approximately 0.101 and 6.923, respectively, which is better than that of RADARSAT-2 (0.132 and 7.206, respectively). Based on the evaluation method of H/α characteristic scattering plane, the overall polarization accuracy of GF-3 and RADARSAT-2 polarimetric SAR is similar, both of which are approximately 0.7. According to the combined factors of intra-class aggregation and inter-class dispersion, the combined factors of GF-3 are 85.34 (water bodies), 28.99 (buildings), and 122.72 (plants). The recognition ability of GF-3 full-polarization SAR images for these three typical features is similar to that of RADARSAT-2. Furthermore, we analyze the characteristics of ground features with different scattering mechanisms and find that the co-polarization measurement accuracy of GF-3 full-polarization SAR is similar to that of RADARSAT-2 but the cross-polarization channel accuracy is slightly worse than that of RADARSAT-2.