Abstract: In order to explore effect of wall thickness on the generation and detection of ultrasound signal, several idealized eccentric pipe models were established based on the finite element method. Effect of different uniform wall-thickness and thickness change at the excitation source, detection point and the propagation path on ultrasonic signal was analyzed. The simulation results show that: when the wall is thinner, the Rayleigh waves cannot be detected; the wall thickness on the propagation path becomes small to some extent, the filtering effect will be so obvious that the high-frequency component is filtered out, but will resume within a certain extent in the pipes with thicker wall. This work will provide a useful guidance for the further application of laser ultrasonic in cylinder nondestructive testing field.