In view of complexity internal structure of mobile hard disk and according to the principle of quality equivalent, a finite element model of mobile hard disk was established. Finite element simulation with dropping impact of mobile hard disk was made based on uniform design. A neural network model of nonlinear mapping relations was established between shell thickness，actuator arm thickness, cantilever thickness and pivot bearings stiffness of mobile hard disk with shell stress，disk interface stress and space with head and disk. The difference is less of the prediction values with the ANN(artificial neutral network) and the simulation datum with the FEM(finite element method). This indicates that the method is effective and may provide theory evidence for optimization crashworthiness design.