Abstract: An effective method is given for designing dynamic vibration absorbers of large complex structures. The structure and interior sound field of a Vehicle are modelled by finite element method(FEM), and the interior noise level of the vehicle is predicted by coupled structure-sound modal synthesis method. An absorber is then designed to be mounted at the bottom of a substructure of the vehicle. As a result the absorber can effectively restrain the vibration of vehicle and markedly reduce the noise in the interior of the vehide. The adults of analysis are in good agreement with the test results.