Abstract:By N–free hydroponic, potted and field randomized block experiments, high efficient soybean rhizobia which were best matched with the rhizobia of mainly planted soybean cultivar, Gongxuan no.1, in Sichuan province were screened from 70 Rhizobia isolated from 33 counties with 35 sampling spots. The results of the first hydroponic experiment show that six strains, S8, S22, S36, S46, S55 and S65, are screened out from 52 Rhizobia which are isolated from 21 counties with 23 sampling spots, and the S8 and S36 are matched “Gong xuan no.1 ” best in the subsequent soil pot experiment. In the second hydroponic experiment, S8, S36 and CK are the positive and negative controls screening, and high efficient strains are screened from the other 12 counties with 12 sampling spots, the results show that plant fresh weights and dry weights of the S151, S152, S150 and S149 are significantly higher than those of CK, and higher than those of the S8 and S36. Consequently, S151, S152, S150, S149 and S8 are used in the field experiment, the results indicate that the yields of S152 and S150 are increased significantly by 33.51%, 18.48% compared with CK, respectively, and the yields of S152 and S150 are also significantly higher than those of the other three tested strains, S151, S149 and S8. Thus, the S152 and S150 rhizobial strains are selected out with best matching “Gong xuan no.1 ”.