Abstract: Abstract: In order to analyze the behaviors of the passive piles under surcharge loads, firstly, a formula for the additional horizontal stress of subsoil is deduced from the modified solutions of Boussinesq. Furthermore, the computational expressions for the soil pressure on the passive side of passive piles are gained. Then, based on the soil movement and stress transfer approach, the distribution of passive load of passive piles is drawn by means of the improved theory of partial plastic deformation. Finally, differential equations for the elastic and plastic section of passive piles are established by using the tri-parameter nonlinear elastic foundation beam model considering theeffect which is caused by lateral load. The original method of combining Matrix-transfer-method with Laplace forward transformation and Laplace inverse transformation is used to solve the deformation and internal force of passive piles influenced by the surcharge loads. The proposed approach is verified by the data from an experiment. The results indicate that the computed and test results are in good agreement. The proposed approach has reference value for studying the bearing mechanism of passive piles due to surcharge loads.