Abstract: The whole trial function was found by the moving least square method in solution domain firstly.And the Galerkin method was used to discretize these controlling function equations.Then the basic function equations of the element-free Galerkin method were built.Considering bending of piles under horizontal load,the meshless method based on large deformation was discussed.According to the above theory,a nonlinear programme was made.In order to verify the theory and programme,horizontal loading tests on pile foundation of Maocaojie Bridge in Hunan Province were performed to provide calculation data.The calculated results were in accordance with the measured data in-situ.This method with consideration of large deformation might be applied in numerical simulation of large deformation rationally and effectively.Moreover,the strength and softening of soil surrounding piles might influence the horizontal bearing capacity of pile greatly.These might provide some references to the engineering projects and analysis of meshless method applied in the pile theory.