To investigate the structure of the pine forest community and the conservation of pine forest in Mt. Sokri, twenty plots of 500$m^2$ size set up by the clumped sampling method. The classification by TWINSPAN and DCA ordination were applied to the study area in order to classify them into several groups based on environmental variables. The plant community was not classified into several groups by above methods in this study area. The successional trends of tree species by both techniques seem to be from Pinus densiflora through Quercus serrata, Fraxinus sieboldiana, Q. aliena, Sorbus alnifolia, Prunus sargentii to Carpinus laxiflora, C. cordata in the canopy layer. and from Rhus trichocarpa, Lindera obtusiloba through Styrax obassia, Acer pseudosieboldiana, Symplocos chinensis for. pilosa to L. erythrocarpa, Viburnum erosum in the understory layer. Pinus densiflora community shall be conserved by the disclimax method, i. e. the broadleaf vegetation in the underlayer of the pine community should be cleared out.