Abstract: The microstructure and wear resistance of AISI 431 stainless steel coatings fabricated on a 42CrMo steel substrate by extreme high speed laser cladding were investigated. Coating processes at low speed (0.6 m/min) and high speeds (20-70 m/min) were compared. The results showed that the 431 stainless steel coating formed by extreme high speed laser cladding was mainly composed of fine equiaxed grains, and iron oxide particles were observed at the interface. With the increase in scanning speed, the friction coefficient of the cladding layer was gradually reduced, the wear scar became more regular, and the wear resistance was significantly improved. When the scanning speed reached 70 m/min, the wear volume was approximately 3.477×10⁶ μm³, with a measured area of about 941 502 μm². The cladding layer exhibited excellent wear resistance, with regular cross-sectional geometry of the wear scar and a peak-to-valley height difference of approximately 30 μm. This study provides a reference for the preparation of wear-resistant coatings on large rotating components such as hydraulic plungers and wind turbine main shafts.