The Lebu Valley in Xizang is one of the hot biodiversity research areas in the eastern part of the Himalayas, and its soil microbial diversity plays an important role in maintaining the stability of alpine mountain ecosystems. In this study, taking the soil microorganisms at eight elevation gradients in Lebu Valley as the research subjects, we utilized Illumina Miseq high-throughput sequencing technology to investigate the distribution characteristics of the diversity and community composition of soil bacteria and fungi along the elevation gradient in Lebu Valley, as well as the factors influencing these patterns. The results were as follows: The soil microbial community diversity in Lebu Valley had different elevation distribution patterns. The soil bacterial and fungal community diversity showed a significant monotonically decreasing elevation pattern. In terms of community composition, the dominant phyla of soil bacteria were Proteobacteria and Acidobacteria, and the relative abundance of Proteobacteria showed a significant decrease and that of Acidobacteria showed a significant increase (P <0.05) with the increase in elevation. The preponderant fungal phyla were Basidiomycota and Ascomycota. Redundancy analysis (RDA) showed that soil physicochemical factors contributed differently to soil microbial communities. The soil bacterial community structure was mainly influenced by pH. The fungal community composition was mainly influenced by EC and Salt. Neutral modelling results showed that stochastic processes played a dominant role in the assembly of soil fine biotopes in Lebu Valley. This study provides a theoretical basis for a profound understanding of the elevation distribution patterns and influences of soil microorganisms in alpine areas.