Background <p>This study compared urinary stone composition and clinical characteristics between Tibetan and non-Tibetan children in Western China.</p> Methods <p>This retrospective cross-sectional study included 237 children (aged 0–14&#xa0;years) with urolithiasis hospitalized at West China Hospital (2008–2023). Stone composition was analyzed via Fourier-transform infrared spectroscopy. Independent associations were evaluated using multivariable logistic regression, alongside a sensitivity analysis restricting controls to Han Chinese (<i>N</i> = 198).</p> Results <p>A total of 237 children were included (Tibetan, <i>n</i> = 121; non-Tibetan, <i>n</i> = 116). Calcium oxalate was the most frequently identified component in both groups (84.0%). Ammonium urate was significantly more prevalent among Tibetan children (35.5% vs. 14.7%, <i>P</i> &lt; 0.001), with this disparity most pronounced among males (38.9% vs. 17.7%, <i>P</i> = 0.004) and toddlers (47.2% vs. 10.3%, <i>P</i> = 0.003). In multivariable logistic regression, Tibetan ethnicity was independently associated with the ammonium urate component across all models (adjusted OR 2.32, 95% CI 1.12–4.80, <i>P</i> = 0.023). The sensitivity analysis restricted to Han Chinese and Tibetan children (<i>N</i> = 198) yielded consistent and stronger effect estimates (adjusted OR 4.10, 95% CI 1.47–11.49, <i>P</i> = 0.007). Tibetan children also exhibited lower Prognostic Nutritional Index scores (<i>P</i> = 0.004) and serum uric acid levels (<i>P</i> = 0.002) across analyses.</p> Conclusion <p>Tibetan children exhibit a distinct urolithiasis profile with elevated prevalence of ammonium urate. This association, most pronounced in young children and males, may reflect nutritional and environmental factors linked to high-altitude residence, underscoring the need for ethnicity-informed prevention strategies.</p> Graphical abstract <p></p>