In this article,the Part Second-Order Second-Moment (PSOSM) probabilistic theory is used to analyze slope reliability,for the slope reliability is related with many random variables and should have random characteristic that can't correctly be reflected by traditional factor of safety (FS). Furthermore,it is difficulty to use FS equations to calculate slope reliability,because most of FS equations are implicit functions,so the explicit virtual function based on slope limit equilibrium theory is used to analyze slope stability.PSOSM and explicit virtual function used together in the slope reliability analysis not only improve the precision of calculation,but also make the process simple. The result of the example given in this article indicates that the idea of above method is clear,the analytic process is simple,and the calculation precision is high. The calculation method of slope is demanded to be more and more accurate,so the method used in this article has a good application prospect.