Abstract: The stability evaluation of foundation pit is an important geotechnical engineering problem. There is strong variability in soil properties of foundation pit, therefore the reliability analysis method is an appropriate method to evaluate the stability of foundation pit. The excavation and support of foundation pit is simulated by elastic-plastic finite elements method, the security coefficient of foundation pit was obtained by the strength reduction method, then its reliability was analyzed by the Rosenblueth statistical moment method. The method is convenient and results are reasonable, which is valuable for the design and construction of foundation pit.