This study was carried out to offer the raw data for the conservation of plant ecosystem in Chungcheongbuk-do with systematic grasping the vascular plant in Mt. Midong and to establish the accurate countermeasure of conservation on the rare species as well as to restore their habitats. The vascular plant species in Mt. Midong were summarized as 303 taxa; 81 families, 215 genus, 262 species, 38 varieties and 3 forms. The rare plants designated by Korea Forestry Service were two taxa; Polygonatum stenophyllum, Hylomecon hylomeconoides. The nine taxa were recorded in the surveyed sites as the endemic plants; Melandryum seoulense, Hylomecon hylomeconoides, Spiraea prunifolia for. simpliciflora, Filipendula palmata var. glabra, Ajuga spectabilis, Weigela subsessilis, Lonicera coreana, Cirsium setidens and Saussurea seoulensis. And the naturalized plants were twelve taxa; Rumex crispus, Lepidium apetalum, Robinia pseudo-acacia, Tyifolium pratense, Trifolium repens, Hibiscus trionum, Oenothera odorata, Ambrosia artemisifolia var. elatior, Erigeron annuus, Erigeron canadensis, Taraxacum officinale and Sonchus oleraceus.