In the past decades, piles have been proven as a useful tool to reinforce the natural slope. However, the slope with stabilizing piles may still fail because of the spatial variability of soil parameters and other natural causes, such as: rain fall, earthquake etc. Therefore, it is essential to assess the reliability of the slope with stabilizing piles. Currently, the reliability analysis studies for the slope with piles mainly focus on the slope failure probability based on the factor of safety. However, the consequence of the slope failure with piles highly depends on the travel distance of the landslides and the research on probabilistic analysis for travel distance after slope failure is very limited. In this paper, we will investigate the probability of its travel distance with stabilizing piles considering the spatial variability of soil parameters based on large deformation analysis. This paper will be outlined as follows. Firstly, the numerical model for analyzing the travel distance of the landslide is described. Then, the most probable failure point of the slope with piles will be obtained based on first-order reliability method. Thereafter, the probability density function of the travel distance will be obtained based on important sampling through refining the results from the first order reliability method. Finally, the suggested method will be applied to an example to illustrate the usefulness of the suggested method, and to investigate the effect of uncertainties in soil parameters on the uncertainty of the travel distance of the landslide. Additionally, the effect on the travel distance probability of different distribution of stabilizing piles will be discussed in this paper. The finding of this paper can help more directly and clearly understand the consequence of the soil slope failure with stabilizing piles and provide reference for stabilizing piles distribution.