Abstract: A C22 nickel-based alloy cladding layer was prepared on the surface of 45 steel for bolts by laser cladding technique. The effects of laser power (1 250‒2 000 W) and scanning speed (80,130 mm · s⁻¹) on the quality of the cladding layer were investigated, and the optimal process parameters were obtained. The phase composition, microstructure, and corrosion resistance of the cladding layers prepared with optimal process parameters were analyzed. The results show that the metallurgical bonding was formed between the cladding layer prepared by different processes and the substrate. With the increase of laser power or the decrease of scanning speed, the width of cladding layer and the depth of heat affected zone increased basically. With increasing laser power, the height of cladding layer increased at the scanning speed of 80 mm · s⁻¹, but decreased at the scanning speed of 130 mm · s⁻¹. At the scanning speed of 130 mm · s⁻¹, the width and height of cladding layer and the depth of heat affected zone were smaller. The optimal laser cladding parameters were the scanning speed of 80 mm · s⁻¹ and the laser power of 1 750 W. Under this optimal process, the height of the single-pass single-layer cladding layer was the biggest, and the cladding layer width and the heat affected zone depth were suitable. The cladding layer was composed of γ-Ni (Cr, Mo, Fe) dendrites and a small amount of MoNi₄ intermetallic compound and molybdenum was enriched in the interdendrite. Compared with the medium temperature of 50 ℃, the free corrosion potential of the cladding layer under the medium temperature of 70 ℃ was lower, the free corrosion current density was higher, the passivation film resistance was lower, and the corrosion resistance was poorer. However, there was still a stable passivation zone in the polarization curves, indicating that the protection was still excellent at 70 ℃. After accelerated corrosion by salt spray for 144 h , the surface morphology of the cladding layer did not change, indicating that the cladding layer had good corrosion resistance.