By Using laser thermal lens spectroscopy, some thermo-optical parameters of materials such as thermal diffusivity with high accuracy can be measured. In this study, the laser thermal lens setup was first arranged. In this system, the second harmonic of the Nd:YAG laser was used. Based on this setup, the thermal diffusivity for glycerol was experimentally measured. The obtained experimental results were compared with the reference results and agreed with them. Then this experiment was simulated by using Comsol software. The results of this simulation showed well the thermal lens process of glycerol under laser irradiation with a wavelength of 532 nm with an external energy range of 100 mJ.