In order to predicting the life characteristics of the rudder, the life aging model of the rudder has been built. The life aging model theory basis has been analyzed, the life aging model of the rudder has been built, based on which, the life of the rudder was predicted, and the acceleration factor constant principle was introduced to deduce the relationships between model parameters on different stresses, by which the simulation was built. The simulation result showed that the acceleration factor constant principle could be used to predicted the life of the rudder under different environment stresses, and compared with the general neural network, the former has stronger stability, which provided a useful reference for the life assessment of the rudder.