This floristic study was conducted from April to September, 2014 in 12 days. The investigated area was Mt. Segeolsan (1,261 m) which is the part of Chirisan National Park and its neighbor region, Goan-ri, Sandeuk-ri. Based on voucher specimens, flora of this area consisted of 108 families, 376 genera, 584 species, 5 subspecies, 73 varieties, and 16 forma, totally 679 taxa. 17 taxa were endemic to Korea such as Carex okamotoi Ohwi, Cimicifuga austrokoreana H.W. Lee & C.W. Park., Thalictrum rochebrunianum var. grandisepalum (H.Lév.) Nakai, Fallopia koreana B.U. Oh & J.G. Kim, Asarum patens (Yamaki) Yamaki ex Y.N. Lee, and Stewartia pseudocamellia Maxim. etc. Among these species, C. austrokoreana, T. rochebrunianum var. grandisepalum, F. koreana, A. patens are considered having a southern boundary line of distribution in the Chirisan National Park region. And so Carex okamotoi has main distribution center in the Chirisan National Park region, this study region is assumed important in phytogeography. The useful plants were 633 taxa, ethonobotanic plants were 359 taxa in this area. Invasive alien species were 61 taxa, which were naturalized rate (9.0%) and urbanized index (17.4%).