In AMT data processing, inversion model construction determines the final inversion, whereas the inversion model of unreasonable deviation leads to erroneous inversion result. Based on thought of previously proposed impression method, the authors made some improvements in this paper: 2D inversion is conducted by using the average resistivity of one-dimensional TM model as uniform half space model resistivity and then, with the inversion result as the element model, the average resistivity as the auxiliary model, and the theoretical probing depth as theimpression depth, a new inversion model is constructed. Comparative studies of examples show that the methods used in this model can better reflect the corresponding geoelectric structure and achieve the balance and unity in the region, thus exhibiting good application effect.