This study is to offer the raw data for conservation and restoration of national park by surveying and analysing the vascular plants in the Gayasan national park. The flora were summarized as 102 families, 328 genera, 469 species, 4 subspecies, 59 varieties and 9 forms. The endangered plants designated by Ministry of Environment were 2 taxa; Pedicularis hallaisanensis Hurus. and Gymnadenia conopsea for. albiflora Y.N.Lee. The rare plants designated by Korea Forest Service were 13 taxa; Crypsinus hastatus (Thunb.) Copel., Ligusticum tachiroei (Franch. & Sav.) M. Hiroe & Constance, Primula modesta var. fauriae (Franch.) Takeda, Lilium distichum Nakai ex Kamibay and so forth. The korean endemic plants were 15 taxa; Betula ermanii Cham., Carpinus laxiflora (Siebold & Zucc.) Blume, Stewartia pseudocamellia Maxim., Galium koreanum (Nakai) Nakai, Heloniopsis koreana Fuse, N.S. Lee & M.N. Tamura and so forth. The specific plants by floristic region were 66 taxa; Betula chinensis Maxim., Spiraea fritschiana Schneid., Vaccinium hirtum var. koreanum (Nakai) Kitam., Cimicifuga heracleifolia Kom., Adoxa moschatellina L. and so forth. The plants with approval for delivering oversea were 22 taxa; Salix hallaisanensis H.L$acute{e}$v., Sanguisorba argutidens Nakai, Viola albida Palib., Weigela subsessilis (Nakai) L.H.Bailey and so forth. The naturalized plants were 30 taxa; Chenopodium album L., Lepidium apetalum Willd., Trifolium pratense L., Bidens frondosa L., Helianthus tuberosus L. and so forth.