Floristic composition and phytosociological studies of Mt. Chongok and Mt. Tuta were investigated, and that was compared with the previously published report in 1993. Vascular plants were composed of 100 families, 358 genera, 573 species, 95 varieties, and 18 formae, totaling 686 taxa. The vegetation was relatively well conserved based on Pteridophyta calculation (Pte-Q), 1.13. Compared with the vascular plants of the southern and northern slope area, the vascular plants of the southern slope area were composed of 87 families, 287 genera, 419 species, 73 varieties, and 11 formae, totaling 503 taxa, and those of the northern slope area consisted of 94 families, 293 genera, 427 species, 73 varieties, and 12 formae, totaling 512 taxa, respectively. Also, compared with the taxa in each side, both sides were composed of 332 species in common, southern sides, 172 species and northern sides, 182 species, respectively. The number of species of 11 families belonged to the higher level among total families taxa was composed of 328 species(47.8%). Among them, Compositae and Rosaceae were included much more species than remnant families. Korean endemic species were composed 16 families, 24 genera, 20 species, 8 varieties and 2 formae, totaling 30 species(4.4%). Compared with the Korean endemic taxa in each side, both sides were composed of 14 species in common, southern sides, 11 species and northern sides, 5 species, respectively. A naturalized plants were 20 species, correspond to 9.2% of totaling 218 species appeared in South Korea. Among them,12 species were appeared commonly in both sides, southern sides, 16 species and northern sides, 16 species, respectively. Life form spectra was H-D1-R5-e type and, useful resources plants are as follows; edible source(42.4%), medicinal source(31.5%), ornamental source(15.6%) and pasture source (13.3%) in the total region. The forest vegetation of the southern slope was classified into 1 order, 1 alliances and 5 communities; Rhododendro-Quercetalia mongolicae, Lindero-Quercion mongolicae, Quercus mongolica Typical community, Populus davidiana-Quercus mongolica community, Pinus koraiensis-Taxus cuspidata community, Pinus densiflora-Carex humilis var. nana community, Betula costata-Betula ermanii community. It is considered that the slight difference of the flora and vegetation in the northern and southern slope is mostly due to the topographical and climatic difference. Even closer investigation is required for the more accurate comparison in this area.