We measured nitrogen, phosphorus, potassium, organic and water content, and SPAD of plant leaves of 25 families and 86 species at different slopes of alpine meadows in Gannan, as well as the soil physicochemical properties, including nitrogen, phosphorus, and organic and water content, to determine variations in plant element content and soil factors at different slope aspects. The relationship between plant leaf nutrient content and soil environmental factors were also analyzed on different slopes. The results showed that soil factors were significantly different at every slope aspect. Specifically, soil phosphorus content decreased successively from northern to southern slopes. Soil nutrient and organic content of northern slopes were much higher than those of southern slopes, whereas they were the lowest on the western slopes. Surprisingly, soil water content of northern slopes was up to 38%, in contrast to soil water content of southern slopes, which were slightly lower. The constituents of plants had meaningful differences at different slope aspects because of the variation in soil factors. Moreover, leaf organic content exhibited little distinct change on different slopes. Leaf nutrient content and SPAD increased from northern to southern slopes, whereas leaf phosphorus, potassium, and leaf water content decreased. Soil factors had significant effects on foliar traits on south-north slope gradients. Increased soil water content enhanced leaf phosphorus, potassium, and water content in plant leaves, and significantly decreased SPAD. Soil nutrient content was significantly positively correlated with plant leaf phosphorus, potassium, and water contents, but negatively correlated with SPAD. The contribution of soil water content and nutrients to leaf element content were different. We concluded that soil water content was the primary factor affecting foliar characteristics and that leaf water content was particularly influenced by environmental factors at different slopes. Leaf water content in southern slope plants in response to soil conditions reinforces that improved water and nutrient use efficiency is an adaptive strategy to drought and barren habitats in the southern slope.