Abstract: Since the shape, size, material and defect of UUT in the infrared thermal wave nondestructive detection are different, three types of uniformity materials with different characteristics were selected by means of the finite element analyze software (ANSYS), and a 3-D sample model was designed to provide the detection with preview of the previous experiment result. The temperature field profiles of the model surface are drawn at different times with the preprocessor and general postprocessor of the software, and then the defect types are confirmed according to the given temperature distribution diagrams. The curves of temperature variation of different defects are drawn based on the analysis of the simulated data. The defect types are determined according to the different slope of the curves. The simulation result indicates that the finite element analyze software can be used for nondestructive evaluation, the simulation result matches with the experiment one. The method can be extended to the detection and the quantitative identification for other kinds of defects under material surfaces.