The identification method of viscoelastic dynamic parameters based on the reflection coefficient measurement of viscoelastic layer in a acoustic-pipe has been developed. Two different types of layers, where one is solid and the other contains cylindrical-hole, will be utilized in the parameter identification. The complex longitudinal speed of viscoelastic material can be obtained through the reflection coefficient measurement of solid sample. Besides of the coefficient measurement of cylindrical-hole sample, the solving of the characteristic equation of viscoelastic-tube should be included in the identification of the complex transverse of viscoelastic material. Then, the complex Young’s modulus and the complex Poisson’s ratio can be calculated easily. Finally, a rubber sample has been tested in the acoustic-pipe, and the identification results of viscoelastic dynamic parameters have been analyzed and discussed.