Laser ultrasound is a technique based on lasers to generate and detect ultrasound remotely. The thermal expansion arising from the optical absorption of a short laser pulse generates ultrasonic wave. By using finite element method, this study presents a source model for laser ultrasonic generation in thin transversely isotropic laminate composite in the thermoelastic regime. According to the thermoelastic theory, the transient temperature is equivalent to a body source to generate ultrasonic waves. The numerical results indicate that the symmetric and antisymmetric Lamb wave is excited in thin transversely isotropic laminate composite plate, the evolution of the dispersive waveform is a function of the source-receiver distance, the plate thickness, and the parameters of the fiber-reinforced composite. These results are very useful for evaluation materials parameters of the composite plate.