Abstract: At present, in the design of deep excavations, with the surrounding soils and conditions permitted, the compound soil-nailing wall supporting form of soil-nailing and prestressed anchor is adopted, which has the advantages of low price and rapid speed for construction, compared to the pile anchor supporting form, so it is widely used in the engineering practice. However, the calculated results of the existing projects empirically designed are relatively conservative owing to the complicated mechanism of action between soil nailing and prestressed anchor. The safety factor of internal global stability is adopted as the objective function, and the global finite-difference method is empbyed to establish the model of sensitivity analysis based on the circular ship slice method. This work will provide important and optimal design basis and even some theoretical basis for the compound soil-nailing wall supporting structure of soil-nailing and prestressed anchor in deep excavation projects.