Abstract: Background With the intensification of global change, land use transformation has become a key factor influencing terrestrial ecosystem functions. Methods This study focuses on the conversion of abandoned land to tea plantations in Yunnan Province, China, aiming to investigate its effects on soil nutrients and microbial communities. Using high-throughput sequencing and bioinformatics analysis, the study reveals significant shifts in soil bacterial communities following land conversion and their implications for nutrient cycling. Results The results indicate that the transformation from abandoned land to tea plantation markedly increased soil organic carbon, total nitrogen, and total phosphorus levels, thereby enhancing multi-nutrient cycling functions. Land use change also significantly restructured the soil bacterial community, with an increase in the relative abundance of Proteobacteria (especially Alphaproteobacteria) and Acidobacteriota in tea plantations, while Firmicutes dominated in farmland. Microbial community succession was primarily driven by factors such as soil organic carbon, total nitrogen, and alkali-hydrolyzable nitrogen, which had notable effects on carbon, nitrogen, and phosphorus cycling. In particular, Alphaproteobacteria and Chloroflexi played key roles in multi-nutrient cycling, suggesting that optimizing microbial community composition is a crucial mechanism for enhancing soil ecological functions. Conclusions These findings provide a theoretical basis for evaluating ecosystem services and guiding the sustainable management of tea plantations.