According to the research status of supporting structure with high-pressure jet grouting pile and composite soil-nailing wall, the paper put forward the selection reason of finite element numerical analysis software Plaxis8.2; discussed selection principle for soil constitutive model and supporting structure material model, and principle for parameter values and step-by-step calculation process. The calculation formula of related parameters for high-pressure jet grouting pile, soil nail and concrete surface layer were mainly given. The paper also studied contribution function of high-pressure jet grouting pile based on representative case example, and introduced application and verification of the above procedure in the design of high-pressure jet grouting pile and composite soil-nailing wall by an engineering case of shopping mall excavation.