This study was carried out to investigate the flora of uninhabited Island in the Deokjeok Archipelago. The vascular plants which were collected in 5 times (from Jun. 2009 to Apr. 2010) were identified as 350 taxa in total, including 89 families, 231 genera, 309 species, 5 subspecies, 31 varieties, and 5 forms. There were many useful plants such as 2 taxa of Korean endemics and 2 taxa of rare plants which were proposed by the Korea Forest Service. The specially determined plants which were categorized as 5 degrees in all by the Ministry of Environment appeared as 49 taxa; Degree V was one taxon; Senecio nemorensis and IV was one taxon; Apocynum lancifolium and III was 2 taxa; Stauntonia hexaphylla, Hylotelephium spectabile and I was 45 taxa; Machilus thunbergii, Neolitsea sericea, Hedera rhombea, etc. Based on the plants which were approval objects when transfer overseas were 5 taxa, and 21 taxa of evergreen plants were recorded in the investigated area. The naturalized plants were identified as 15 taxa, and their naturalization ratio were found to be 4.2% respectively.