The coupling mechanism between soil enzyme activity and nutrient factors in the Qinghai-Tibet Plateau ecosystem has a profound influence on soil biogeochemical cycling processes. Assessing this coupling relationship is crucial for understanding the stability and resilience of high-altitude ecosystems. This study focused on six typical native vegetation areas in the Ali Region of Tibet, collecting soil samples from the 0–20 cm surface layer. The samples were analyzed for available nutrients (available phosphorus, available potassium, ammonium nitrogen, nitrate nitrogen), organic carbon, total nitrogen, total phosphorus, total potassium content, and the activity of four key soil enzymes (urease, phosphatase, sucrase, and catalase). Kruskal–Wallis H tests, Spearman correlation analysis, and RDA redundancy analysis were used to assess their spatial variability characteristics and nutrient-driven mechanisms. The results showed significant spatial heterogeneity in soil enzyme activity and nutrient levels across different vegetation zones, with the highest enzyme activity levels observed in areas dominated by Stipa capillaris (N_05) and Avena fatua (N_06). Soil enzyme activity showed a significant positive correlation with key nutrients (particularly available phosphorus, nitrate nitrogen, and ammonium nitrogen) (P ≤ 0.05). The study results revealed the sensitive response mechanism of soil microbial function to nutrient supply in high-altitude special ecosystems, providing data support for the functional maintenance and restoration of vegetation in cold-arid ecosystems.