A pulsed fiber laser with a wavelength of 1064 nm is used to clean the epoxy silicone paint on the surface of KMN steel. The overlap ratio and energy density are selected as variable parameters, and the samples are cleaned in one pass and two passes under different parameters. The effects of laser cleaning parameters on the substrate surface roughness and the adhesion of the recoating paint are investigated, as well as the trends and reasons for the variation of substrate surface Vickers hardness with the cleaning parameters. The results show that with an energy density of 4.73 J/cm² and an overlap ratio of 0.4-0.7, the paint cannot be removed by a single pass cleaning, and a second pass cleaning is required to remove the residual paint chips. When the overlap ratio of the second cleaning is less than 0.5 and the energy density is less than 4.25 J/cm², the substrate surface melting causes a minor decrease in the surface roughness, but the adhesion of the recoating paint is unaffected at surface roughness of more than 0.6. When the overlap ratio of the second cleaning is greater than 0.5 and the energy density is greater than 4.25 J/cm², the surface tensile stress caused by melting and solidification of the substrate surface, as well as the phase change and grain growth in the heat-affected zone, resulting in a lower hardness on the substrate surface compared to the interior.