This paper presented a theoretical model of l oss factor of metalrubber. Dynamic experiments on a metalrubbe r structure were made. Effects of the material density and the heat treatment te chnology on the l oss factors of the structure were investigated qualitatively, and eff e cts of the heights of the material and the weights of the system on the loss fac tors wer e also studied quantitatively. The relation between the two pa rameters and the loss factor was obtained by the least square method. The loss factor of the structure was predicted, and the result established a theoretica l foundation for analysis of dynamic response of metalrubber.