In order to study the effect of reinforcement of entire basal soil on the deformation and stress of foundation pit, the effect of the reinforcement of entire basal soil at the bottom of foundation pit on the ground surface settlement, the lateral displacement of top beam, the bending moment of pile and the earth pressure behind pile was studied by laboratory model test.The ABAQUS finite element software was used to simulate the model test and the experimental data were compared with the numerical results.The effects of cement-mixed ratio and reinforcement depth on the deformation of foundation pit were analyzed.The results show that the effect of reinforcement of entire basal soil is the most obvious to reduce the bottom heave, the lateral displacement of retaining structure is more obvious, and the ground surface settlement is not obvious.The range analysis method shows that increasing the elastic modulus of reinforced soil is more effective than increasing the reinforcement depth to restrain the lateral displacement of supporting pile and the soil heave of foundation pit.When the cement-mixed ratio exceeds a certain range, the reinforcement effect is not significantly improved.It is suggested that the cement-mixed ratio is generally 5%~20% in the soft soil area with 20% water content.When the soil reinforcement depth exceeds a certain range, the effect of controlling the deformation of foundation pit is improved but not obvious.It is suggested that the soil reinforcement depth should be 0.4~0.45 times the depth of foundation pit.