Laser cladding has been taken into consideration for repairing K418 Ni-based superalloy material with CoCrNiW powder.Composition of cladding materials was revealed by energy dispersive X-ray spectrum(EDS). The characteristic microstructure of the cladding layer and interface were investigated by using an optical microscope and scanning electron microscope(SEM).Cladding coatings were obtained for different process parameters, and a detailed study of the effects of these parameters has been carried out by SEM. Metallurgical bonding between the cladding layer and substrate materials was obtained.Effect of heat input on cladding cracking susceptibility has been studied to obtain optimum condition for crack-free welds. Variations in cracking susceptibility as a function of heat input is discussed with reference to metallurgical characteristics of the clads. The corresponding microstructure induced by different heat input was discussed in this paper too.