Abstract: To investigate the diversity of culturable fungi on the surface of tobacco leaves during aging, 25 domestic and imported samples of normal and mildewed tobacco leaves of different qualities were collected. Plate isolation and molecular biology methods were adopted to identify and analyze the culturable fungi on tobacco leaves. In total of 415 culturable fungi were identified, and the ITS sequences of 77 representative strains were analyzed. The results showed that:1) The diversity of fungi on mildewed leaves was higher than that on normal leaves. 2) Except for 7 uncertain strains, the other 70 strains belonged to 3 phyla, 8 classes and more than 30 genera. The dominant genera were Aspergillus, Cladosporium and Rhizopus, accounting for 22.9%, 7.1% and 7.1%, respectively. 3) The unique genera (Aureobasidium, Myrmaecium and Coniochaeta) were isolated from imported tobacco leaves during aging. These results indicated that the diversity of culturable fungi on flue-cured tobacco leaves during aging was high and the category of fungi more closely correlated to tobacco growing areas. Furthermore, limiting the growth and reproduction of Aspergillus was a key step for reducing the incidence of mildew on tobacco leaves during aging.