Abstract: The occurrence of fault belt must change the hardness of rock mass.The translation speed of Rayleigh wave is related to physical and mechanical properies of medium.The Rayleigh wave survey technique is used for water-bearing fault belt pre-pretection in the process of a tunnel construction of Quansan highway,and the result is compared with the result of ground penetracting radar.It is indicated that the Rayleigh wave technique is a kind of simple,effective technique for pre-detecting water-bearing fault belt in the process of the tunnel construction.