Microorganisms are key drivers of saline-alkali soil ecosystems,and culturable microbes provide essential inoculum resources for biological remediation.In this study,culturable microbial diversity in saline and non-saline soils at different depths across four regions of Gansu Province was investigated using isolation–cultivation and molecular identification.A total of 477 bacterial isolates and 424 fungal isolates were obtained.Correlation analysis and PCA revealed that salinity and depth jointly shaped microbial community structures;significant correlations were observed among non-saline soils across regions,whereas MinQin(MQ) and JingYuan(JY) showed highly significant correlations in saline soils.Functional predictions indicated pronounced differentiation in bacterial functions,while fungal functions remained relatively stable.This study elucidates the culturable microbial community characteristics and environmental responses in arid-region saline-alkali soils,providing practical microbial resources and theoretical support for subsequent saline-alkali soil remediation.