Abstract:In the background of the study on a certain type of missile, according to the professional, the missilewas divided into eight subsystem, such as projectile, engine systems, electronic and electrical equipment, etc.Adopting FTA and FMMEA methods, the failure modes and mechanisms were analyzed. The severity level andoccurrence probability level of failure modes were introduced to construct the failure mode risk assessmentmodel, the failure hazardous degree of the missile’s sub-systems was quantitatively analyzed. According tothe missile site failure data during service and combined with prior information, and based on the Bayesian es.timation, the calculating method of occurrence probability level of each failure mode was put forward, the fail.ure sorting sequence of missile sub-systems was given and the weak links were determined, and providing sup.port for the subsequent prediction of storage life.