Abstract:To study safety performance of elastic structure subjected to random explosive load, based on finite volume method (FVM) a numerical method used to calculate structural reliability index was presented. The partial derivative of responses with respect to basic random variables were obtained with governing equation of FVM; and then the mean values and variances of responses were got based on Taylor expansion; and structural reliability index was calculated by First-Order Second Moment finally. To prove the feasibility of this method, considering explosive charge、distance from structure to explosive and yield stress as basic random variables, the reliability index of a clamped plane subjected to far field explosion was calculated. Compared with response surface method and Monte-Carlo method, the result indicates the method has a higher efficiency and precision, and can be applied in engineering practice effectively.