the results of laser cladding process depend on temperature distribution, thermal stress fields and geometrical deformation during the manufacturing process, study of these results is vital. By simulation of the process, the thermal characteristics during manufacturing three-layer process using Nd: YAG laser and materials;IN-738 for substrate and NiCoCrAlY for powder were studied.The results show that by increasing clad height, the maximum temperature increases and the melt pool can be larger, therefore the powder efficiency and height of the next clad increase. The numerical results show that adding 2% nano-CeO2 and pre-heating reduce the ratio of the maximum thermal stress to the maximum temperature and hence prevent to formation of cracks and delamination in clads.