The purpose of this study was to analyze forest vegetation type classification in Mt. Dutasan for understanding information of ecologycal management. Data were collected by total of forty six plots using Z-M phytosociological method from June to October, 2016, and analyzed by vegetation classification, importance value, environment factor using coincidence and interspecific association analysis. As a result of vegetation type classification, Quercus mongolica community group was classified at a top level of vegetation hierarchy that was classified into Rhododendron schlippenbachii community and Betula costata community. R. schlippenbachii community was divided into Lychnis cognata group and R. schlippenbachii typical group. L. cognata group was subdivided into Veratrum oxysepalum subgroup and L. cognata typical subgroup. B. costata community was divided into Fraxinus mandshurica group and Betula schmidtii group. F. mandshurica group was subdivided into Weigela subsessilis subgroup and Cimicifuga heracleifolia subgroup. Therefore the forest vegetation was composed of six vegetation units with two kinds of bisected species groups and fourteen species groups. Mean importance percentage of vegetation unit 1 was showing Q. mongolica 31.6%, Acer pseudosieboldianum 13.2%, Tilia amurensis 11.8%, that of unit2 was Q. mongolica 42.0%, A. pseudosieboldianum 15.6%, Fraxinus rhynchophylla 6.8% that of unit3 Q. mongolica 25.4%, Acer pseudosieboldianum 11.4%, A. mandshuricum. 9.7% that of unit4 F. mandshurica 10.1%, B. costata 9.2%, P. maackii 8.1% that of unit5 F. mandshurica 11.2%, Abies holophylla 10..0%, B. costata 8.1% that of unit6 P. maackii 13.2%, B. costata 13.1%, S. commixta 9.9% in the order, respectively. According to the correlation between vegetation unit and environmental factor, R. schlippenbachii community(vegetation units 1～3) and B. costata community(vegetation units 4～6)were classified based on 1,100m of altitude, middle slope, twenty of slope degree, twenty percents of bare rock. R. schlippenbachii community(vegetation units 1～3) showed positive correlation with altitude, topography and B. costata community(vegetation units 4～6) showed negative correlation tendency with them. As a result of interspecific association, forest vegetation was divided into two groups. And it was considered that the vegetation type by could be affected by Altitude and topography.