The Mt. Cheongok is located at the northern part of Kyungsangpookdo from 37°00` 00`` to 37°05` 00`` latitude and from 128°55` 00`` to 129°00` 00`` longitude. The altitude of the summit is 1,276.5m. This study was carried out to classify forest communities by the methods of Zurich-Montepellier schools. And, it also might be useful for selection of plant species, forest conservation, and prompting vegetation succession. The forest vegetation in Mt. Cheongok was classified into 12 communities, 4 groups, and 4 subgroups. Rhododendron micranthum subgroup of Pinus densiflora for. erecta community and Fraxinus mandshurica community were not found in cool temperate forest, southern zone yet. According to the coincidence method, Pines densiflora for. erecta community was mainly distributed from altitude 450m to 1,100m and from upper slope to ridge, and Quercus mongolica community was dominanced in the range of over altitude 700m. Pinus densiflora for. erecta community, distributed in upper slope and ridge, is judged to be maintained in the future. But Pinus densiflora for. erecta community, distributed in below middle slope, is judged to be changed into deciduous hardwood forest.