Rupture of descending thoracic aorta is a rare but lethal disease.Compared with open surgery,thoracic endovascular aortic repair (TEVAR) becomes a less invasive procedure in emergent management of patients with feasible anatomy.Nevertheless,mortality remains high as well as morbidity despite successful operation.The purpose of this study was to compare TEVAR with conservative therapy on the 30-day mortality of patients with ruptured descending thoracic aorta.Methods Retrospective analysis of patients admitted to our hospital with descending thoracic aortic rupture was performed.Patients presented with rupture of descending thoracic aorta with feasible anatomy for TEVAR between Jan 2014 and June 2019 were included.Patients were divided into operative and conservative group depending on which therapy they received.Patients received TEVAR were defined as the operative group,while those received conservative therapy were defined as conservative treatment group.Results There were twenty-six patients in total,including fifteen aortic dissections,nine were thoracic aneurysms,and two were traumatic injuries.Theie mean age was 60±13 years with only two female.Seven patients (27％) presented with shock and twenty-two (85％) was accompanied with hemothorax on admission.Nineteen patients (73％) accepted emergent TEVAR with 100％ primary technical success,and the other seven received conservative treatment.In operative group,infection (89％) and respiratory failure (63％) occurred after TEVAR.The in-hospital mortality for operative and conservative treatment group was 26％ and 57％ respectively (P=0.18).Operative group had lower 30-day mortality (26％ vs.86％,P=0.021).Conclusions TEVAR is associated with improved early outcome in patients with ruptured descending thoracic aorta.