Forest biomass is influenced by multiple factors. The growth of trees shift in strategy altered with change of temperature and precipitation even for the same tree species in different regions, which would remodel the biomass allocation patterns. 150 pieces of masson pine(Pinus massoniana)grown in south China were studied. And the related information of the sample trees were recorded including spatial location(longitude and latitude), mean annual temperature ( MAT ), mean annual precipitation ( MAP ), tree diameter at breast height(DBH)and tree height , tree barks, stems, branches, foliage and roots. The one-way ANOVA and path analysis methods were employed to investigate the relationship between organs biomass with the influencing factors. Coefficient of variation based on the results of path analysis was used to test biomass sensitive degree to change in temperature and precipitation of organs difference and regional difference. The results showed that the sensitivity of biomass to the increasing MAT varied with organs which was in a sequence as roots> branches> bark> stems> foliage. While for the sensitivity to the increasing MAP, it was arranged as barks> branches> foliage> roots> stems. The sensitivity of masson pine biomass to changes in MAT and MAP also was significant difference in regions which presented a pattern of northern subtropics> mid-subtropics> southern subtropics with a decreasing difference from north to south. Organs biomass is significantly correlated with DBH and tree height (P < 0.05). P. massoniana biomass was found to have significant correlations with DBH (P < 0.001), which had the greatest direct influence coefficients with values close to 1. Whereas, tree height that exerted influence on biomass through DBH had the greatest indirect influence coefficients close to 1.%林木生物量受多重因素的综合影响，同一树种在不同区域内水热因子的变化也可能会影响树木各器官生物量的分配关系。选择南方150棵马尾松为研究对象，采集样木所在的空间位置（经度、纬度）、年均温度、年均降水、胸径、树高等相关因子，测定树干、树皮、树枝、树叶、树根各器官生物量。运用方差分析、通径分析等方法，分析北亚热带、中亚热带、南亚热带内马尾松各器官生物量与影响因素的关系，利用变异系数探讨了不同气候带马尾松生物量对水热变化敏感程度的器官差异和区域差异。研究结果表明：（1）马尾松各器官生物量对温度升高的敏感程度表现为根最高，叶最低，按大小顺序为根＞枝＞皮＞干＞叶；各器官生物量对降水增加的敏感程度表现为皮最高，干最低，按大小顺序为皮＞枝＞叶＞根＞干。（2）马尾松生物量对温度和降水变化的敏感程度的区域差异明显，空间上呈现出北亚热带＞中亚热带＞南亚热带，从北往南敏感程度逐渐减小。（3）胸径和树高因子均与各器官生物量存在显著相关关系（P＜0.05）。胸径对各器官生物量的直接通径系数接近于1（P＜0.001），树高通过胸径影响生物量的间接通径系数接近于1。
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