Altitude is an important driver on the spatial pattern of plant nutrient stoichiometry,and closely related to plant physiological processes and regional biogeochemical cycles. Study on the relationship between altitude and plant leaf nutrient stoichiometry contributes to forecast responses to global change. In this study,we explored the leaf C,N and P stoichiometric characteristics and their relationship with altitude in the north and south areas of the Tianshan Mountains. The results showed that average leaf C,N and P concentrations in the central Tianshan Mountains were (414.3 47.3), (21.4 8.1) and (1.39 0.64) mg·g ~(- 1),and the average leaf C∶N, C∶ P and N∶P were 18.7 7.3,288.6 133.9 and 15.4 5.8,respectively. Leaf C and P concentrations were significantly higher in the north than those in the south of the Tianshan Mountains,but leaf C∶P and N∶P were significantly lower in the north than those in the south. There was no significant difference in leaf N and C∶N between the two parts of the mountains. Nutrients and their ratios were significantly correlated with each other,except for C vs. C∶P in the north and C vs. N,P and N∶ P in both parts. Leaf nutrients showed the similar altitudinal trends in plants sampled from both sides of the Tianshan Mountains: leaf P increased,and leaf C,C∶P and N∶P decreased with increasing altitude; but there was no significant linear relationship between leaf N and altitude in the study area. It was suggested that the different hydrothermal conditions and decoupling between elements contribute to the spatial patterns of leaf C,N and P stoichiometry at the two sides and along the altitudinal gradient of the Tianshan Mountains.