Abstract: A multilayered viscoelastic model of pavement is established. Based on the dynamical analysis of nondestructive FWD data, a system identification method is used to backcalculate the material properties of the media. The forward analysis is done through an analytical method in the frequency domain. Numerical results show that the backcalculation process is stable and convergent. The system identification method is effective and applicable to the dynamic property identification of pavement structures.