This study aims to investigate the distribution of the useful resources plants and the flora of Deogyusan. The flora of Deogyusan was investigated from April in 2002 to November in 2003. Vascular plants of this area consist of total 549 taxa; 9 forma, 64 varieties, 476 species, 281 genera, 90 families. It corresponds to $13.5\%$ of totally 4,071 taxa appeared in Korea. Useful plants of this area were investigated 399 taxa. It corresponds to $72.5\%$ of collected plants in this area under our study. Among the useful plants, there are 205 taxa of edible source, 179 taxa of pasture source, 159 taxa of medicinal source, 70 taxa of ornamental source, 15 taxa of timber, and 17 taxa of industrial raw materials. Korean endemic plants were composed 18 families, 23 genera, 19 species, 4 varieties and totaling 25 taxa.