Abstract: WC particles reinforced Ni-based spray-welding coating were prepared using Ni-WC mixed powder on normalizing treatment 45 steel surface by oxyacetylene spray welding technique, the microstructure and chemical composition of the coating were analyzed by SEM and XRD, and the effect of WC content on the coating hardness and abrasive resistance were discussed. The results show that the microstructure of the coating was fine, and the metallurgic combine of the coating and matrix was well. The hardness and abrasive resistance of the coating showed an earlier raising and later decreasing with WC content. When WC content was around 35wt%, the mechanical properties were optimal: the hardness was 1 250 HV and abrasion quantity was 0.06 g.