Abstract: Based on the expression of precursory displacement field,the expressions of stress,tilt,groundwater and earth resistance are given,and the feasibility to inverse potential focal parameters with multiple precursory data is discussed.Since these expressions have the same unknowns of x,y,h,α,β,if we use the precursory data above mentioned sufficiently,the combining inversion should be feasible.But since the affection of local condition and apparatus drifting,the data are usually not uniform with the results,so many technical problems need solve in calculation.