The significance of numerical analysis of foundation pit excavation lies in the selection of soil constitution and reasonable calculation parameters and hardening model is one of soil constitutive models that are used widely. First of all, the SS-HCA GDS system and oedometer apparatus are used to complete a large number of laboratory tests, which are obtained the prime parameters of hardening model(HS) model in Nanchang and established the relationship among the modulus. The experimental results are compared with those of domestic and foreign literatures. Then, the PLAXIS finite element numerical calculation software is used to conduct numerical simulation of a deep foundation pit project in a basement in Nanchang. The soil constitution adopted the programmed HS model. The results show that the calculated value of horizontal displacement of retaining pile is in good agreement with the measured value. The HS model and the determination method for parameters are proved to be applicable in numerical simulation of excavation engineering in Nanchang area. It is of reference and application value to similar engineering.