Abstract: Aiming at the laser remanufacturing of gas corrosion crack in the root of the FV520(B) steel blade for air blower, remanufacturing process parameters were optimized through orthogonal experimental analysis. Through analyzing the breakage in the root of FV520(B) steel blade simulator, the repairing scheme for laser scanning was planned, the metallographic structure and phase composition of the repaired region were observed and analyzed, the hardness was also tested. The results show that, the 1.1 kW laser power, the 250 mm/min scanning speed, the 8.10 g/min power feeding rate, the 150 L/h carrier gas flow are the optimized process parameters for special material and remanufacture system,the multi-scanning paths are synthetized to decrease the thermal cumulative effect between layers, the dimension precision between the repaired and the original one is 0.8 mm, there is strong metallurgical bonding between the cladding layer and the substrate, the hardness of the cladding layer surface is the highest, its average value is 675 HV0.2, the interface can reach 610 HV0.2, the cladding layer has better metallographic structure and hardness property.