Abstract: The surface layer soil is effected by multiple factors after excavation. Without consideration of external force and geometric parameter, the failure is mainly enslaved by cohension, gravity and inner frictional angle. Firstly, the failure zone of the slope is calculated by Mindlin solution when single factor is changing in feasible scope. Then, with reference to the slope stability sensitivity analysis, taking the analysis of the curve expressing the failure zone, and taking the horizontal distance between the curve and the surface of the slope as evaluating indicator, it can be obtained that the sensitivity of the effected factors from high to low is cohension, gravity and inner frictional angle.