Abstract: The quenching modified layer was prepared by fiber laser on the surface of 440C steel.The effects of different laser powers on the microstructure evolution, hardness, wear properties and corrosion resistance were investigated.The results show that austenite and martensite are formed on the surface of the material after laser quenching, and the microstructure is fine. The maximum microhardness can reach 650 HV, and the maximum hardening depth is 0.3 mm. With the increase of power, the friction coefficient decreases, the wear resistance improves, the self-corrosion current density decreases, and the corrosion resistance improves.