Abstract:Maize Dwarf Mosaic Disease is a main virus disease of maize, and the most effective way of dealing with the disease is the breeding of resistant varieties. The combination of conventional breeding methods and molecular breeding technology can greatly improve the disease-resistant breeding efficiency. In this study, two molecular markers Indel186-9 and SCAR112 developed in previous study were used to identify the genotype of 100 maize inbred lines, and combining phenotype identification, the validity of two molecular markers was investigated for marker-assisted selection(MAS). The results suggest that there were few highly resistant varieties of the germplasm resources and the resistance is pressingly needed to be improved. Inbred lines used in this experiment were made of various blood, and the resistance materials mainly come from PB and sipingtou germplasm. The selection accuracy of both Indel186-9 and SCAR112 were up to 80%, and the selection accuracy of the two markers used simultaneously for MAS was up to 91.67%，among which the resistant selection accuracy was up to 100%. The two markers improved the average resistant level from 7.26 to 2.4 and 7.63 to 4.27 respectively. It proved that the two markers can be used to select resistant materials of maize dwarf mosaic disease, and the right combination can improve the efficiency of selection.