Abstract: Based on the discussion of the theory of electrical resistivity tomography (ERT),Miller soil box is adopted to perform a standardized laboratory procedure for measuring soil electrical resistivity. Through orthogonal test,it is discovered that the influences of electrical resistivity decrease in such an order: water content, pore-water electrical conductivity, degree of saturation,type of soil. The correlation between electrical resistivity and soil physical indexes is also thoroughly studied in this paper. Then, an electrical resistivity model and its Archie’s parameters of typical clay are established. Finally, A practical demonstration is given to illustrate the ability to find potential object by ERT.