In one traffic accident, the commercial vehicle that was in developing stage crash to the wall because of the error operation of the driver. In the accident, it was found that the hinge of the engineer hood was fractured. It was very dangerous for the driver and the passengers, and that also lead the energy absorbing ability reduced. The limitation of the design also was showed in the standard test that the vehicle crash to the rigid wall at the speed of 50km/h. The simulation result and the really crash test both show that the hinge of the engine hood fractured in the test. To solve the problem, the design of the outer and inner panel was changed, and the new material, such as high strength steel, was applied. The simulation results show that the new design could improve the crashworthiness of the vehicle greatly.