Abstract: The dominant population structure and dynamics of the Yukeng forest community in Xianju County of Zhejiang Province were analyzed by using the method of spatial sere substituting for time sere,which comes to the following conclusion:The distribution diagram shapes of the evergreen broad leaved trees of different size among the dominant populations are basically similar.The populations survival cures are of sharp linear,and the age structure is stable.The age structure for deciduous trees Alniphyllum fortunei is declining.The distribution patterns of Castanopsis eyrei,Cyclobalanopsis glauca and Machilus thunbergii populations are of clump;the distribution patterns of Schima superba and Daphniphyllum oldhamii populations are mostly of poisson;the distribution pattern of Alniphyllum fortunei is of poisson or uniform.The distribution patterns of seedling and treelet of Castanpsis eyrei are of clump while the medium,big sized trees are of poisson or uniform.