Abstract: Internal disbonds of translucent laminates were not detected successfully in some cases of infrared pulsed thermography (PT). To investigate the reason, based on the heat theoretical analysis and the optical parameters of experimental measurements, the energy distribution of body heat in PT for the studied objects, glass fiber laminates, was obtained.A simulation of PT was performed by 2D modeling, and the inner heat stimulated by illumination was imitated by inner heat-generating.A comparative analysis of the translucent model and the regular model was conducted using the finite element analysis. The results show that the translucent property can lead to failure in PT. The depth and size of a defect that could not be detected were calculated by applying detectable defect signal standard to the simulation results, and it was testified that raising the pulsed energy could contribute to the defect inspection of translucent materials.