Introduction: Thromboangiitis obliterans (TAO) has been characterized as an inflammatory disease predominantly affecting young male smokers. The epidemiologic spectrum of TAO has evolved, with increased proportion of women and non-smokers. However, sex-based differences among patients with TAO in real-world datasets remain unclear. Research Question: How do the TAO prevalence and limb amputation rate differ between women and men in a real world dataset? Methods: We assess sex-based differences in a large, administrative Nationwide Inpatients Sample (NIS) 2016-2019. The diagnosis of TAO and variables were identified by ICD-10-CM codes. Univariable comparisons between female and male patients were assessed by Mann-Whitney. Multivariate logistic models were used to analysis associations between sex and TAO prevalence, and cumulative limb amputation, adjusted with demographics characteristics and comorbidities. Results: In this cohort study of patients with TAO (N=836), 301 (36.0%) of them were women and 535 (64.0%) of them were men. TAO prevalence rate showed 96.4% higher in men compared to women ( Fig. 1A , female:7.28%ooo, male: 14.30%ooo, p<0.001), with adjusted odd ratio (OR) at 1.51 ( Fig. 1C , 95% CI, 1.30-1.76; p<0.001) for male. The cumulative limb amputation rate was up to 32.9% in male patients and 20.9% in female patients ( Fig.1B , p<0.001), with adjusted OR at 2.22 ( Fig. 1C , 95% CI; 1.51-3.26; p<0.001) for male patients. Conclusions: Male patients showed significant higher TAO prevalence and cumulative limb amputation rate. Notably, although TAO is a rare vascular disease, the cumulative limb amputation rate was up to 32.9% in male and 20.9% in female patients. The sex-based disparities spur further studies on subgroup analysis, mechanism, health equity and multidisciplinary management for patients with TAO.