The high-speed laser deposition process can improve the corrosion problem of conventional cladding coatings. In order to study the effect of scanning speed on the microstructure and properties of cladding coatings, Inconel 625 coatings were prepared on 300M steel substrate with different laser scanning speed. The microstructure, phase composition, hardness and corrosion resistance of the coatings prepared at 40 m/min and 70 m/min were analyzed. The results show that the metallurgical morphology of Ni-based alloy coating prepared at different scanning speed is mainly cellular and columnar, and the phase composition is mainly composed of γ-Ni solid solution and Fe3Ni2. The hardness of high-speed laser cladding layer increases with the increase of line scanning speed, the corrosion potential increases and the corrosion current density decreases gradually. With the increase of scanning rate, the uniformity of the coating is improved, and the dilution ratio, grain size and heat input are significantly reduced, and the diffusion of interface elements is inhibited, so the corrosion performance of the material is significantly improved.