During the reliability analysis of supporting structure in underground engineering, more reasonable reliability computing methods would like to be adopted because of large discreteness of parameters of soil-rock mass and high-degree of nonlinearity of performance function, as well as nearly manifesting as implicit function. While it is hard to satisfy the project requirement by traditional Monte Carlo simulation method with large amount of computation work, the finite element reliability program of joint computation including Matlab and Abaqus is developed. It combines the advantages of Matlab and Abaqus based on Latin hypercube sampling and has the outstanding feature of saving sample space and improving efficiency of sampling as well. It can easily converge and satisfies requirements of reliability analysis of supporting structure by exhibiting a case of a circular tunnel in underground engineering.