A 70-year-old woman with a history of bypass surgery for coarctation of the aorta (CoA) at approximately 10 years of age was referred to our hospital after a descending thoracic aortic aneurysm was discovered during a preoperative examination for uterine cancer. Contrast-enhanced CT revealed a 62×47 mm aneurysm in the descending thoracic aorta, connected to the bypass vessel, leading to the diagnosis of an anastomotic pseudoaneurysm following CoA surgery. Due to the large diameter of the aortic aneurysm and the high risk of rupture, we performed a left axillary artery to left femoral artery bypass in addition to thoracic endovascular aortic repair (TEVAR). Postoperative CT indicated no endoleak, and the patient was discharged after uterine cancer surgery with an uneventful recovery.