Abstract: Based on the results of numerical simulation, this paper studied the influence of in homogeneous geoelectrical structure on the signals of geoelectric filed. It mainly in-cludes influence of inhomogeneous geoelectrical structure on the geoelectrical field pro-duced by natural electro magnetic induction and the abnormal geoelectric field produced. near the hypocenter area. The results show that the bigger the difference of the electricalfeature between the inhomo geneous body and its country rock is,the more influence the inho mogeneous body exerts on the geoelectric field; the larger the special dimension of the in homogeneous body is the more influence exerts on the geoelectric field. The existence of the inhomog eneous geoelectric structure also produces an important influence on the form of the ground distribution of the abnormal geoelectric field coming from hypocenter areas in the model, in which the seismogenic areas are regarded as a kind of charge source. The special distribution of abnormal geoelectrical fieldis closely related to the existence of in-homo geneous medium beneath the surface.

Key words: Geoelectric field, Magnetotelluric apparent resistivity, Electric inhomogene-ity, Earthquake precursor information