As the direct tool of metal deforming in rolling, the quality and operational life span of mill roll are of high significance. Mill roll is the main consumption component with a high ratio in steel rolling production costs. In this paper, the indefinite chilled cast-iron roller is surface-modified by laser cladding, using Cr2C3 and NiCr powder. The results indicates that, the cladding layer and base materials are a good metallurgical bond, and the microstructure of cladding layer is finer than base materials. The average microhardnesses of base materials and cladding layer are 506 HV and 1137 HV, respectively. Compared with the base material hardness, cladding layer hardness increases by 25%, so the wear resistance of the cladding layer is significantly improved. Microcrack in cldding layer includes solidification crack and low plasticity crack, and the microcrack is effectively decreased by the secondary scanning and adjusting chemical composition of the powder.