Abstract: In order to clarify the resistance of Hubei origin germplasms of air-cured and sun-cured tobaccos to powdery mildew, 88 germplasms of air-cured and sun-cured tobacco were evaluated in greenhouse by spraying inoculation with the fungal isolate kept by Tobacco Research Institute of Chinese Academy of Agricultural Sciences. The results showed that the resistance to powdery mildew differed significantly, 13 were highly resistant (HR), 39 moderately resistant (MR), 18 moderately susceptible (MS), and 18 highly susceptible (HS) among the total 88 germplasms. The highest resistant ones were LC04, ZX06 and WF04, with relative resistant indexes of 0.99. The highest susceptible ones were FJY01 and CY08, with relative resistant indexes of less than 0.1. The results of variance analysis indicated that the differences of infected leaf ratio, disease index and relative resistant index reached significantly levels (p < 0.05) between different resistant types. The 88 germplasms were clustered into HR, MR, MS and HS groups by DPS data analyzing software.