Aiming at the influence of uncertain ties on the vehicle structural crash worthiness, are liability-based design optimization (RBDO)method for vehicle structural crash worthiness based on hybrid model was proposed.First,a RBDO model for vehicle structural crash worthiness based on probability and interval hybrid model was established,and the nesting level was analyzed.Then,in order to reduce the nesting,an efficient decoupling strategy was proposed,which transformed the original nesting problem into a single-layer design optimization problem.Finally,the approximate RBDO problem was constructed by using the radial basis function.The local densifying strategy was employed to improve the accuracy of the results.The research results show that the method converges rapidly,and the RBDO problem of vehicle structural crash worthinessis solved quickly.It has a wide application prospect in the field of vehicle crash worthiness design optimization,which has cer- tain reference value for the design optimization of vehicle structural crash worthiness.