The carbon (C), nitrogen (N) and phosphorus (P) stoichiometry of plant leaves could reflect the adaptive strategies of plants to environmental changes, which is one of the hot issues in ecological stoichiometry study. Research on the variation in leaf stoichiometry of related species along environmental gradients is significant for in-depth understanding of plants' nutrient strategies. However, the results of changes in leaf stoichiometry along altitude gradients are not consistent in previous studies. In this study, we collected leaves of four Quercus species, including Q. aliena, Q. variabilis, Q. aliena var. acuteserrata, and Q. wutaishansea in Taibai Mountain from 1100 m to 2200 m. Leaf C, N, P concentrations were measured and analyzed to explore the variations along the altitudinal gradient. Meanwhile, we quantified the influences of climate, soil and topographic factors (i.e. the slope of land) on the variations of leaf C, N, P and C ∶ N ∶ P ratio. The results showed that 1) overall, leaf C of the four species increased first and decreased then with the elevation, leaf N and N ∶ P decreased and leaf C ∶ N increased with the elevation. 2) Variations of leaf stoichiometry were different among the four species. Similar to Q. aliena var. acuteserrata, leaf N and P of Q. aliena decreased but C ∶ N increased with the elevation. However, leaf N and C ∶ N of Q. variabilis showed opposite trends. Leaf C of Q. wutaishansea decreased with the elevation, but the variation in leaf P and N ∶ P showed nonlinear trend. Specifically, leaf P of Q. wutaishansea increased first and decreased then along the altitudinal gradient, while the trend of leaf N ∶ P was opposite. 3) The main impact factors for the variations of leaf stoichiometry were different. Leaf N and C ∶ N in leaves were mainly influenced by climatic factors, with 39.91%─36.59% variation explained. Leaf P, N ∶ P and C ∶ P were mainly affected by soil and landform factor (explaining 23.70%─39.83% variation), and influenced by the interaction between them was significant (explaining 16.24%─24.72% variation). The results indicate that: 1) when facing and dealing with environmental change, even closely related species could exhibit different spatial patterns and nutrient strategies, which could explain their zonal distribution to some extent. 2) The topographic factor could affect stoichiometry of plants together with soil factors, and the slope of land is also an important factor which should be considered in leaf stoichiometry studies of mountain forest ecosystem.