This study was carried out to investigate flora of Golji stream watershed in Gangwon province. The vascular plants which were collected in 11 times (from May 2012 to Nov. 2013) were identified as 825 taxa in total, including 124 families, 420 genera, 730 species, 8 subspecies, 78 varieties, 6 forms and 3 hybrids. In the flora of this area, Korean endemic species were 34 taxa, red list of vascular plants according to IUCN valuation basis were 34 taxa and 165 taxa of specially designated floristic regional indicator plants by the Ministry of Environment. Among those species investigated in this survey, 101 taxa were identified as specific species bio-geographically as compared to flora of other terrestrial regions; 37 of calcicolous plants, 64 with distribution in the northern part of the Korean peninsula. 34 aquatic taxa and 69 naturalized plants were recorded in the investigated area.