Stochastic finite element method was used to analyze the reliability of the bearing capacity of strip footings considering the spatial variability of soil undrained shear strength. The influence of degree of non-stationarity and spatial correlation length on the mean and standard deviation of bearing capacity was analyzed by using stochastic finite element method combined with Monte Carlo simulation method. The failure probability and safety factor of foundation under various parameter combinations were calculated and coMPared. The results show that the bearing capacity of the strip footing increases with the increase of the degree of non-stationarity, and its bearing capacity decreases firstly and then increases with the increase of spatial correlation length.