Fagaceae plants are one of the most important components of subtropical evergreen broad-leaved forests. To study the carbon (C), nitrogen (N) and phosphorus (P) contents and metrological characteristics of different tree species and organs is of great importance for understanding and predicting the ecological functions of trees. In this study, 5 species of Fagaceae in the same forest community in Yinnashan Provincial Nature Reserve were studied to explore the content, stoichiometry and correlation characteristics of C, N, P among different species and organs. The results showed that: (1) The organ and tree species had certain effects on C, N, P contents and stoichiometric ratio of plants, and the interaction between the two was significant (except C content), and the limiting degree was organ>tree species. (2) In terms of content, litter N was generally higher than that of stem and root, while litter P was generally lower than that of stem and root, and the contents of N and P in the seedling leaves were lower than those in mature tree leaves. The root N and N ∶ P of Castanopsis fissa were higher than those of other species, while the root P was lower than that of other species. (3) From the perspective of interspecific variation coefficient, the variation coefficient of root N, C ∶ N, and N ∶ P was significantly higher than that of other organs; From the point of view of inter-organ variation coefficient, the variation coefficient of N and C ∶ N was significantly lower than that of other species. (4) From the perspective of nutrient correlation between tree species and organs, the correlation between most of the organ elements of the five plants was not significant, indicating that the nutrient metrological relationship of a single organ could not directly reflect the metrological relationship of other organs or the whole tree level; The correlation between C and N, C and P varied with tree species, but the relationship between N and P was highly consistent with each tree species. In summary, from the perspective of organs, the root N content, C ∶ N, and N ∶ P had the largest interspecific coefficient of variation, which may be attributed to the difference in N and P uptake by different tree species, which is conducive to species coexistence. From the point of view of tree species, C. fissa has more rational nutrient distribution pattern, which is conducive to maintaining a dominant position in community competition.