Abstract: The study of Dracontomelon macrocarpum community in Xishuangbanna is based on phytocoenology.Dracontomelon macrocarpum(Anacardiaceae) and Pometea tomentosa(Sapindaceae)are the upper dominant species of the community.The community are divided into A,B,C and D layer.The community is mainly charactered by evergreen megaphaenerophytes and mesophaenerophyteswith simple,characeous,entire,caudal mesophylls.There are many woody lianas and epiphytes in the layers.The biological diversity in the community is rich.It is the north extension of the tropical seasonal rain forest of Laos.The individual number of trees is few.The dynamic structure is stable is stable,the distribution area is limited,its ecosystem so fragil that cries out for urgent protection.

Key words: Xishuangbanna, Dracontomelon macrocarpum, Community, Phytocoenology