Abstract: Though damping matrix estimation is a choke point for dynamic modeling, it is an important parameter for structural dynamic analysis. In this paper, a damping matrix identification method for vicious damping structures is proposed. An advantage of this method is that different manners of nonzero values in damping matrix can be considered, and the other is that real damping matrix can be estimated reasonably utilizing the first limited lower order frequencies and corresponding complex mode shapes, which can adapt to the status that only the first limited lower order modes can be measured in field. A 5-DOF spring-mass-damping system is employed to validate the proposed method. Numerical results indicate that: 1) the resulted damping ratios can match perfectly with the measured values by employing the proposed method, and 2) a real damping matrix can be estimated reasonably by utilizing the first limited lower order frequencies and corresponding complex mode shapes.