Introduction Turner syndrome (TS) seriously impacts women's health and quality of life, yet research on its global burden remains limited. This study aimed to evaluate the burden and between-country inequalities of TS using global population data.Material and Methods Data on prevalence, years lived with disability (YLDs), and incidence of TS were obtained from the Global Burden of Disease (GBD) 2021 database for comprehensive analysis. Geographic and socioeconomic disparities were assessed using decomposition analysis, cross-country health inequality analysis, and frontier analysis. Future trends were projected using an autoregressive integrated moving average (ARIMA) model.Results In 2021, TS accounted for an estimated 531 784 (95% UI: 420 532-697 786) prevalent cases, 9177 (95% UI: 4254-15 926) YLDs, and 23 929 (95% UI: 17 948-32 035) incident cases globally. From 1990 to 2021, the numbers of prevalence and YLDs increased by 27.7% and 29.2%, respectively, while their ASRs remained stable. Decomposition analysis indicated that population growth was the main driver of increases in prevalence and YLDs. Persistent between-country inequalities were observed: prevalence and YLDs were predominantly concentrated in high Socio-demographic Index (SDI) regions, whereas incidence remained higher in low-SDI countries. Frontier analysis revealed notable efficiency gaps in high-SDI countries, while low-SDI countries were near optimal levels. The ARIMA model projected a steady rise in the absolute number of TS cases from 2021 to 2050, alongside slight declines in age-standardized prevalence, YLDs, and incidence rates.Conclusions The global burden of TS has continued to rise, accompanied by persistent between-country disparities. These findings highlight the need for improved disease management strategies and more equitable resource allocation to address the growing burden.