Bark, the outermost structure of the stem in woody species, plays important roles in protecting stem, nutrient storage and transportation. Therefore, bark thickness is a very importantly functional trait, and its variation not only affects various ecological functions of bark, but also affects community construction and species coexistence. However, previous studies on the bark thickness focused on the fire-prone ecosystem. Bark thickness in fire-free subtropical evergreen broad-leaved forests has still not been investigated. In this study, we measured the bark thickness of woody species in a subtropical evergreen broad-leaved forest in Gutianshan National Nature Reserve (GNNR), and examined the variations of bark thickness, including total bark thickness (TBT), inner bark thickness (IBT) and outer bark thickness (OBT), at species, family and functional group levels. The results showed that:1) the TBT, IBT and OBT of 807 individuals from 39 species were 1.90 mm, 1.38 mm and 0.54 mm, respectively. The family Anacardiaceae, Myricaceae and the dominant families like Fagaceae and Theaceae had larger TBT, IBT and OBT, as well as species as Quercus serrata, Schima superba, Cyclobalanopsis myrsinifolia. 2) There were significant differences in TBT, IBT and OBT among species and among families, respectively. Among different functional groups, the TBT, IBT and OBT of tree species were larger than those of shrub species. The TBT and IBT of evergreen species were larger than those of the deciduous species. In this study, bark thickness in the subtropical evergreen broad-leaved forest community of GNNR is relatively thinner than that of the fire-prone ecosystem, indicating the adaptability of these species to the local humid climate. The significant variation of bark thickness reflects the coexistence of different ecological strategies within the community.