Introduction: Optimal treatment for type B aortic intramural hematoma (IMH) is not well defined. Here we report clinical and imaging outcomes in type B aortic IMH patients given thoracic endovascular aortic repair (TEVAR) treatment and compare outcomes to those given medical treatment. Methods: In the type B aortic IMH population in the FRAD (Fuwai Registry of Aortic Dissection) study between Sept 25, 2010, and Aug 17, 2017, we assessed all-cause mortality and incidence of strokes, and aortic IMH progression after initial diagnosis. Then we analyzed clinical and imaging outcomes in this population between those patients treated with TEVAR or medical treatment, using multivariate Cox regression and logistic regression models. Results: After the initial diagnosis, 38 of 347 patients (27.4% female and the mean age was 60.3±11.1 years) with CT imaging confirmed type B aortic IMH in the cohort had died (5 years all-cause mortality 11·2%; 6.1% in the TEVAR subgroup and 14.0% Medical subgroup, p=0.003). Radiologically confirmed strokes had occurred in 8 (3.4%) patients. COX regression model revealed TEVAR treatment was associated with decreased risk of mortality (HR=0.59, 95% CI 0.37 to 0.93; p=0·02). Among 244 patients (157 in TEVAR and 87 in medical subgroup) who has CT imaging data available for analysis, resolving of IMH in descending aorta occurred in 103 Patients (53.5% in the TEVAR subgroup and 33.3% in the medical subgroup, p=0.003). Logistic regression model revealed that TEVAR treatment significantly increase the probability of aortic remodeling (resolving of IMH) in descending aorta (HR=2.5, 95% CI 1.4 to 4.5; p=0·001). Conclusion: TEVAR treatment in type B intramural hematoma patients is associated with lower all-cause mortality compared with medical treatment. Cox regression and logistic regression analysis indicate a significant superiority for defined outcomes (survival and aortic remodeling) with TEVAR treatment compared with medical treatment, suggesting that TEVAR treatment might be the preferred treatment in type B intramural hematoma patients. Disclosure: Nothing to disclose