[Aim] The invasive plant Cenchrus spinifex can proliferate and expand its population in poor sandy soils with limited phosphorus, forming a single dominant community. Analyzing the efficient utilization mechanism of phosphorus by C. spinifex under phosphorus stress can provide a theoretical basis for revealing mechanism of its invasion.[Method] Four treatments of C. spinifex, Agropyron cristatum, Setaria viridis, and CK (soil without plants) were established. The compositional differences of phosphorus-solubilizing bacteria in soil were analyzed from the perspective of soil phosphorus-solubilizing microorganisms using high-throughput sequencing technology.[Result] The results showed that the invasion of C. spinifex significantly improved soil phosphatase activity and the community diversity of soil phosphate-solubilizing bacteria. PCA and UPGMA clustering results showed that the species composition of phosphorus-solubilizing bacteria in the rhizosphere of C. spinifex and A. cristatum was similar. The multi-level species difference discriminant analysis results showed that the phosphate-solubilizing bacteria groups were significantly enriched in the rhizosphere of C. spinifex and significantly different from other treatments were Alphaproteobacteria and Streptomyces, which may play important roles in the absorption of phosphorus by C. spinifex. Total phosphorus content in the rhizosphere soil of C. spinifex was significantly positively correlated with the presence of Proteobacteria, Planctomycetes, and Actinobacteria, and there was a close relationship between Actinobacteria and available phosphorus content in the rhizosphere soil of C. spinifex.[Conclusion] C. spinifex indirectly affected the phosphorus environment of the rhizosphere soil by changing the community structure of phosphorus-solubilizing bacteria in the rhizosphere soil of the invaded soil, which is beneficial for its growth.