Leaf functional traits can respond to the changes of environmental conditions and reflect adaptation strategies of plants to environments. At present, there are few studies on the geographical pattern of leaf functional traits and their environmental drivers of lianas. Here, we measured 15 leaf functional traits of an endangered liana species Monimopetalum chinense (Celastraceae) in 11 populations across its natural distribution range in China, and combined climate factor and soil factor to explain trait variation. We investigated the extent of trait variation at local and regional scales, and analyzed the influence of environmental factors on leaf traits by multiple stepwise regression. The coefficients of variation of leaf functional traits was different, the fold range of variation of leaf traits ranged from 1.03 to 1.80 times. The traits variation value of local scale was higher than regional scale. At regional scale, the coefficients of variation of leaf traits functional ranged from 1.1% to 15.5%. At local scale, the coefficient of variation of leaf traits functional ranged from 3.0% to 22.5%. Among these two scales, the variation degree of leaf area was the largest and the variation degree of leaf carbon content was the smallest. The morphology of the leaves was affected by the latitudinal gradient, leaf length-width ratio decreased significantly as latitude increased, and the leaf morphological factor increased significantly as latitude increased. Leaf shape became wider and more round as latitude increased to increase the thickness of the leaf boundary and reduce the hydrothermal dissipation of the leaves. Leaf phosphorus content was relatively low, and the soil available phosphorus content in the distribution area of M. chinense was also low, indicating that the growth of M. chinense might be limited by phosphorus. There was no any single environmental factor could explain all leaf trait, the association between environmental factors and leaf functional trait was complex. Soil and climate factors were strong predictors of leaf trait, and 25%-97% of leaf trait could be explained. Soil pH, soil nitrate nitrogen, and soil available phosphorus were the dominant pridcetors for the of leaf traits of M. chinense, the mean annual temperature and annual precipitation could also affect the of some leaf traits. Under the condition of sufficient temperature and water, the leaf of M. chinense tended to be a conservative strategy of slow growth. Overall, M. chinense leaves adapted to environments by intraspecific variation and combination of traits, as well as the associations with climate and soil factors.