It is very important to comprehend the characteristic of wave propagation in FGM plate for the material detecting without injury. The law of PSV wave propagation in inhomogeneous FGM plate were studied. The dispersion relations of PSV wave propagation in the functionally graded material plate were obtained by using the method of WKBJ. The approximate analytical solution of PSV wave propagation in the FGM plate was derived. The method of numerical calculation was provided. An example of Metal（Ni）- Ceramic(Tic) Practical FGM plate model, the dispersion relations of PSV wave propagation in the FGM plate with different material parameters were studied. And the displacement curves along the cross section were plotted,when plate thick changed, the wave number was changing accordingly , corresponding to the same phase velocity,the coupled wave numble decreased accordingly along with the plate’s thick incresing ,when plate’s thick remian unchanged,the ingredient ratio of material changed, the wave number was changing accordingly,when the metal content ratio decreased gradually,the coupled wave number increased accordingly ,under same phase velocity,dispersion cave slopes gently corresponded to wave velocity increasing.