The present research conducted microbial community analysis on small fragments collected from the Torazuka Tumulus to clarify the structure of microbial communities on wall paintings without biodeterioration by using molecular biological methods.As a result of quantitative PCR using the DNA solution extracted from the small pieces of wall paintings, the number of fungal 18S rRNA genes within all samples were less than that of bacterial 16S rRNA genes.The results from the next-generation sequencing of viruses have shown that the following phyla have appeared frequently in all samples: Proteobacteria (relative abundance 27.9%-50.9%), Bacteroidetes (8.8%-46.9%), Planctomycetes (3.2%-15.1%) and Acidobacteria (2.2%-3.7%). Genus Reyranella in phylum Proteobacteria and genus Chryseolinea in phylum Bacteroidetes have shown the highest relative abundance within all samples.Results from the clone library analysis have shown that the genus Exophiala had the highest relative abundance within all samples. As Exophiala has also been isolated from the Takamatsuzuka Tumulus, Kitora Tumulus, and Lascaux cave, it was suggested that stone surfaces such as burial mounds are favorable habitats for Exophiala.In the future, it is necessary to clarify the interaction between the bacteria and fungi from small fragments using the culturing methods. Furthermore, basic research such as the abundance of bacteria and fungi in stone chambers, and their interaction with biological communities, including soil animals, is needed. These studies are expected to provide important knowledge to understand local conservation methods for wall paintings in the Torazuka Tumulus
