Abstract：There are two aspects influencing on stabilization planning，which are theoretical analysis method and selection of the mechanical property parameters of soil and rock mass. Limit equilibrium theory is one of the normal mathematical approach，in which physics meaning is determinacy，in stability analysis of soil and rock mass. But the result of stabilization computation and the potential slip surface are intensely affected by the mechanical property parameter. The randomness of the mechanical property parameter is only considered in the normal failure-safe analysis model but the restraining characteristic of the determinacy mathematical model and random change of the mechanical property parameter are not contained. The planning of slope stability with method of chance constrained theory means that the restraining conditions of the determinacy mathematical model and randomness of the mechanical property parameter are inverted as the equivalence class of failure-safe analysis model. So the reliability index of slope could be obtained under the condition of the defined slip surface based on searching calculation. In the paper，the analysis idea is shown with an example.
