Abstract: Surface roughening is very important in arc spraying, as the coating quality depends greatly on its treatment result. By means of the orthogonal test and the variance analysis, the influence of dry blasting steel grit parameters on blasting result and bond strength of arc spraying was conducted. The optimized technology standard was given. The surface roughness obtained by this technology was approached to the Nation Standard of the Peoples Republic of China. The bed test of diesel engine indicated that the optimized dry blasting steel grit and arc spraying technology was feasible to repairing crankshaft.