Abstract: Base on the surface borehole induced polarization（IP)forward modeling of 3D finite difference method，this paper proposes a method for building partial derivative matrix with the optimized inversion scheme and choose inversion parameters by polarization body theory analytical formula. The scale transformation method and conjugate gradient method are used to solve problems about inversion and by the combination of finite difference forward simulation for surface borehole IP measurement data.The result shows that we obtained the inversion results and the fitting effect with better precision，and the inversion method has certain valuable feasibility and applicability.