This study was carried out to analyze community character and classify forest community with phytosociological method and quadrat method to forest of Mt. Busosan in Buyeo-Gun.1. Communities by phytosociological method were classified into Pinus densiflora community and Quercus sp. community. With the classification of TWINSPAN, the community was categorized into Pinus densiflora - Quercus variabilis community and Pinus densiflora - Styrax japonica community.2. The importance value of Pinus densiflora, Quercus acutissima, Prunus sargentii, Styrax japonica, Quercus serrata, Quercus variabilis, Pinus rigida, Quercus aliena in tree layer were 83.20, 41.87, 30.93, 24.85, 23.27, 20.97, 20.28, and 9.46, respectively. The relative coverage of Stephanandra incisa, Quercus serrata, Styrax japonica, Parthenocissua tricuspidata, Rhododendron mucronulatum, Lindera obtusiloba, Prunus sargentii, Quercus variabilis, Indigofera kirilowii, Quercus acutissima, Lespedeza maximowiczii, and Acer pseudosibolianum in shrub layer were 9.62%, 9.55%, 9.18%, 7.85%, 6.18%, 5.25%, 4.82%, 4.15%, 3.98%, 3.98%, 3.55%, and 2.98%, respectively.3. According to size distribution map of diameter breast height of dominant species, the dominant species of Mt. Busosan was Pinus densiflora, and Quercus sp. such as Quercus acutissima, Quercus variabilis, and Quercus serrata may compete with the Pinus densiflora in the future.4. According to the ordination analysis of Mt. Busosan forest, Pinus densiflora - Styrax japonica community was found in moist site and Pinus densiflora - Quercus variabilis community was found in dry site.