Distribution of vascular plants in Yangyang-gun were investigated 12 times from Apr. to Sept., 2008. In the result of survey, the flora of this area consist of 412 taxa totally; 89 families, 259 genera, 366 species, 5 subspecies, 37 varieties and 4 forms. There were remarkable plants such as 11 taxa of Korean endemic plants, 58 taxa of specific plants which were designated by the Ministry of Environment, 2 taxa of endangered plants of Ministry of Environment, 7 taxa of rare, endangered plants of Korea Forest Service and 28 taxa of afforestation plants and 296 taxa of useful plants. Furthermore, 36 taxa of naturalized plants (8.74%) were also observed in this area. Vegetation of investigated area was conserved well. However, vegetation has been destroyed rapidly due to construction of commercial complex for human recreation such as condominiums and stores. Therefore, it is need to efficient management of the water quality and vegetation by conservation strategies from huge visitors.