Taking account of the temperature-dependence of the thermal physical parameters, the thermoelastic generated ultrasound and transient temperature fields by pulsed laser in mono-layer and double-layer materials are numerical simulated by finite element method. In the mono-layer plate, whose thickness is less than the central wavelength of the generated ultrasound, Lamb wave, mainly with a non-dispersion symmetric mode and a dispersion anti-symmetric mode, is obtained by numerical simulation. When the sample thickness increases so that the higher modes can propagate in the plate, a skimming surface longitudinal wave and a Rayleigh wave are formed at the sample surface. Furthermore, the normal displacement on the surface of two kinds of two-layer system, one is Ni/Al systems and the other is Al/Cu system, is calculated. Because the high frequency surface acoustic wave due to less penetration depth is more influenced by the properties of the surface layer during propagating and the low frequency surface wave is more influenced by the substrate, normal dispersion is observed in Ni/Al system and anomalous dispersion is observed in Al/Cu system, respectively.