Abstract: The reliability method is one of effective ways to deal with the uncertainty existing in engineering structures.Due to the existence of hybrid uncertainties in many engineering structures,a reliability method of hybrid uncertainties is proposed,and it is suitable for engineering application.Based on the interval reliability model of the volume ratio,a non-probabilistic reliability model for the structure with fuzzy-interval hybrid variables is established by transforming the fuzzy variables into the interval variables.The presented hybrid reliability model can be used as a supplement to the previous methods,as it has a clearer meaning and it is reasonable to deal with the fuzzy information.The proposed model was used in the optimization design of an airfoil,and the numerical example shows that the method is effective and feasible.