Climbing plants are prone to become fire ladders when forest fires occur, igniting the crowns of host trees and thus triggering crown fires. To evaluate the flammability of climbing plants in the forest, the old living leaves of main climbing plants located in Chuxiong Prefecture, Yunnan Province, were taken as the study objects. Six leaf morphological traits indicators of leaf length, width, thickness, area, specific leaf area, and moisture content, were measured. A self-designed burning device was used to conduct leaf combustion experiments, and three leaf flammability parameters, namely whether ignited or not (ignitibility), burning time (sustainability), mass loss (consumability) were recorded. The differences in interspecific leaf flammability were compared, and the relationship between flammability and leaf morphological trait were analyzed. The results showed that: (1) The living leaves of 6 climbing plants, namely Hedera nepalensis var. sinensis, Anredera cordifolia, Craspedolobium unijugum, Periploca calophylla, Lonicera japonica, and Mucuna sempervirens, were non-flammable. The other leaves from 8 climbing plant species were flammable. The order of their leaf flammability was: Ficus sarmentosa var. henryi>Smilax mairei> Embelia vestita> Callerya dielsiana> Cocculus orbiculatus> Tetrastigma obtectum>Jasminum officinale>Euonymus fortunei. (2) The leaf ignitibility was related to its thickness, area, specific leaf area, and moisture content. The thicker the leaves, the larger the area and specific leaf area, the higher moisture content, the lower the leaf ignition probability. The leaf sustainability was positively correlated with leaf area and moisture content, and negatively correlated with specific leaf area. The leaf consumability was positively correlated with leaf area and negatively correlated with moisture content and thickness. The research results can enrich the data on the relationship between flammability and functional traits of climbing plants in subtropical region, provide references for the selection of fire-resistant plants and fuel management in Chuxiong Prefecture, and lay a foundation for further fire risk identification and evaluation of climbing plants.