Abstract：Taking Janbu mode in sliding surface can be random shape for example，the complex calculation process of stability coefficient and nonlinear characteristics of its final expression for slope under limit equilibrium theory are analysed. Obstacle due to nonlinear characteristics for slope stability coefficient when analyzing its reliability is pointed out. To solve above-mentioned problem，a solution in which small samples statistical learning method based on structural risk theory is regarded as tool which transforms high nonlinear problem in low dimensions space into simple linear problem in high dimensions. An analytical process for slope stability coefficient under Janbu mode is used to research and deduce transitional function expression，iterative method for stepwise approach checking point，calculation of reliability and so on. A new analytical method，based on learning theory of small samples for slope stability reliability，is established. Stability for two slopes which have developed a run-through soft surface are analyzed by the new method. It is found that the computation cost of the new method is 0.6% of accurate method；the absolute error of the calculation result is about 0.195% and relative error is 1.25%.
