Abstract: The traditional calculation of stability analysis of landslide is impacted by many factors, such as the different properties of soils and rocks, the random variation of external factors, the inhomogeneity of geological bodies and the errors of sampling, etc. The final results are adopted excessive manual intervention. According to the law of large numbers of mathematical statistics, the landslide failure probability model has been established more practically by introducing the Monte-Carlo method to the original analysis method. So taking the road landside around Ankang city for example, the landslide in three kinds of conditions was calculated respectively with the model mentioned before, and makes the results more correctly and comprehensively.