Abstract: This paper deals with competition among three species (Phoebe bournei,Betula luminifera and Ilex formosana) in Luoboyan Nature Reserve of Fujian province. The relative densities of these species are taken as the measurement of niche overlap and their competitions are analysed by comparing K ratios with competition coefficients with the results that Betula luminifera will be replaced by increasing Phoebe bournei and Ilex formosana populations. Ilex formosana population can coexist with Phoebe bournei population while present density of Phoebe bournei population is larger than that of Ilex formosana population. The results show that LotkaVolterra competition equation together with K of the Logistic model is practical to predict population dynamics in this research. The process of competition is closely related to ecological characteristics of these different populations.