The electrical anisotropy in the crust and the upper mantle is the main link among geoelectrical model, underlying structure, and tectonic model. In recent years, great attention was paid to this phenomenon, which promotes the new research towards the structure model of electrical anisotropy and inversion theory. According to the Marquardt's inversion theory, in the paper we first improve the weighting factor and apply it to the apparent resistivity and impedance phase joint inversion. Then, the detailed example analysis of them proves the corrctness of the mentioned theory. Additionally, the processing and the interpretation of the measured magnetotelluric data in northwest of china not only indicate the practicability of the theory, but also provide a new method for the future research of deep electrical structures.