Abstract:In order to study growth characteristics of natural population of chinese pine(Pinus tabulaeformis) in the western limit of its distribution, two study sites were set up in the pine forests in Beishan with six plots and in Dongshan of Qinghai Province with five plots, Results from examining the tree height-DBH relation of individuals in populations showed that the pine forest in Dongshan was sparse considerably and its maximum tree height, an index of potential productivity of population, was 14–20m only, about 50% of that in Beishan. The fact that ratio of tree height to DBH of individual was negatively correlated to the individual size standed that individual with a smaller size had a stronger adaptability to suppressed light environment than one with a larger size. There was a clear distinction between DBH growth curves in Beishan and in Dongshan, which DBH increment decreased with an increase of population age in Dongshan, while showed an increasing tendency or unclear change with population age in Beishan. plant biomass in these two sites was greatly different, having a mean value of about 200t/ha in Beishan and 100t/ha in Dongshan. The aboveground biomass density(ABD)in these two sites had insignificant difference, a range of 7-11t/ha.m. By using the linear relationship between ABD and total basal area at breast height, the method of estimating aboveground biomass could be formulated. The relationship between population density and mean dry weight of the natural pine population was also discussed in this paper.