Abstract: In order to comparatively analyze the applicability of the α, β and γ arrays of high density resistivity with tri-potential electrode in prospecting several kinds of common geological bodies, such as the bedrock surface, the water-bearing fault and the filled underground hollow, first, the authors built some pertinent resistivity geologic models to calculate their resistivity and then add noise to execute two dimensional resistivity inversion, then some engineering application instances have been used to verify the forward simulation results and do further analysis. The analysis results of the forward simulation and application instances show that the β array has the best resolution in detecting the water-bearing fault and the filled underground void when there is almost no topography and other interferential conditions, the α array is the ideal device of exploring the bedrock surface, but when there exist some topography interference, the α and γ arrays will be the best device to detect the underground void and nearly vertical fault respectively.