Abstract: The application of damping technology in vibration damping and noise reduction has being developed by leaps and bounds in decades.There has not been yet a normal method to determine the physical parameters of viscoelastic materials and their structures, such as loss factor and modulus of elasticity,etc.Although there are many methods to measure the physical parameters,most of them are only applicable for materials.The resonance measurements and time-decay-rate measurements,the ordinary manners for measuring the structure damping,are not suitable for high damping structures.In this paper a new thchnique is put forward to determine the physical parameters of high damping structures,which is by aid of a microcomputer and its interfaces to search the free decay waves along the cantilever and on the basis of theory of linear approximation to obtain the physical parameters of structures. The sources of varies errors are discussed as well.The technique proposed is particularly effective on high damping structures.