The invention discloses a laser rapid repairing method for high alloy, and belongs to the technical field of laser cladding. The method comprises the steps that step 1, a to-be-repaired spheroidal graphite cast iron roller is machined to remove a fatigue layer; step 2, the to-be-repaired spheroidal graphite cast iron roller is locally heated; step 3, the roller is coated with a transition layer bythe laser, wherein the HRC40-degree alloy is selected as the material of the transition layer; step 4, the roller coated with the transition layer in the step 3 is machined for the second time, and the thickness of 0.5-1.5mm is reserved; step 5, the roller is coated with a surface layer by laser; and step 6, the roller coated with the surface layer in the step 5 is machined for the third time toremove burrs. According to the method, through the research and development and integration of super-thick and large-area laser rapid three-dimensional forming complete equipment , the component design of the cladding material, determination of the process parameters and the like, the remanufacturing technology level of the spheroidal graphite cast iron roller and the high-end key parts of the spheroidal graphite cast iron roller is remarkably improved.