Abstract: In order to improve surface performance of H13 steel, Ni-based coatings were fabricated on H13 steel surface with YLS-4000 fiber laser. On the basis of orthogonal test and analysis, superficial status, geometric parameters, dilution ratio, microstructure and hardness of coatings under different processing parameters were obtained and investigated. The results show that coating surface is uneven when laser power is minimum (1800W) and powder feeding rate is maximum (1.0g/s). Coating surface has cracks when laser power (2200W) and scanning speed (25mm/s) are maximunm. When dilution ratio is lower than 10%, average hardness of cladding zone is improved to more than 800HV and is more than 3 times of substrate hardness (246HV). Strengthening effect is remarkable. When dilution ratio is larger than 25%, hardness of bottom layer in cladding zone is low due to the dilution of substrate. With the increase of laser power and scan speed, dilution ratio of the coating increases while dilution ratio decreases with the increase of powder feeding rate. Coatings of good quality with smooth surface, compact texture, and remarkable strengthening effect can be obtained by adjusting processing parameters.