Abstract: Combining basic Surface Acoustic Wave (SAW) theory with reported recursive stiffness matrix method, this paper deduces an effective permittitivity mathematical model of Rayleigh wave based on ZnO/Diamond/Si-layered structure through separating the Rayleigh wave from SAW. By this model the dispersive figures including phase velocity and electromechanical coupling coefficients are calculated. The calculation results show that the model has good accuracy and reflects well the dispersion properties of Rayleigh wave. Furthermore, an effective permittitivity mathematical model of three layers from solving basic wave equations is derived. At last, two important parameters which are used in designing SAW devices are calculated.