Abstract: Take the rhizosphere soil of alfalfa as research object, the rhizosphere and non-rhizosphere（control） soil were collected, and high-throughput sequencing technology of 16S rRNA was used to study the rhizosphere bacterial community characteristics of alfalfa in severe saline-alkali land of Ningxia′ north, in order to provide reference for improving the saline-alkali land by planting alfalfa and using microbial resources of saline-alkali land.The results showed that, soil enzymes activities and microbial diversity in the rhizosphere of alfalfa planted in saline-alkali land.The pH of the sampling area was 8.57,and the salt concentration was 669.51 mg·L^-1,which belonged to the middle and severe saline-alkali land.The activities of phosphatase, sucrase and urease in alfalfa rhizosphere soil were significantly higher than those in non-rhizosphere soil.A total of 10 488 OTUs were obtained by high-throughput sequencing, distributed in 94 phyla, 191 classes, 391 orders, 549 families, 910 genus and 448 species.The dominant phylum were Proteobacteria, unidentified＿Bacteria, Bacteroidota, Acidobacteria and Gemmatimonadetes.The dominant genus were Halomonas,Pseudomonas,unidentified＿Actinomarinales and Azoarcus.The relative abundance of dominant bacterial genera Halomonas,Pseudomonas,and Azoarcus was significantly higher in rhizosphere soil than in non rhizosphere soil.