Abstract: Under the complex service load, the seventh stage impeller disc of CO₂ compressor appeared a "through-crack", which greatly affected the safety of production. In order to restore the function of impeller quickly and efficiently, temperature field of laser cladding process and technology were studied. A finite element model of layer by layer was established and temperature field was acquired to optimize process parameters. Design and experiment of the remanufacturing scheme for damaged impeller were carried out, and the quality test and Installation test were carried out. The results show that the temperature of impeller in the initial stage decreases and the input of heat source needs to be increased; the quality testing of impeller remanufacturing, including the bonding strength of remanufacturing area, non-destructive testing, dynamic balance testing, industrial CT and fluorescence testing, all meet the requirements of standards; the test machine is tested successfully once and meets the production requirements of enterprises. Remanufacturing experiments and applying verify the design scheme is reasonable and laser additive process is reliability.