BACKGROUND Massive upper gastrointestinal (GI) bleeding is usually urgent and severe, and is mostly caused by GI diseases. Aortoesophageal fistula (AEF) after thoracic aortic stent grafting is a rare cause of this condition, and has a poor prognosis with a high mortality rate. The clinical symptoms of AEF are usually nonspecific, and the diagnosis is often difficult, especially when upper GI bleeding is absent. Early identification, early diagnosis, and early treatment are very important for improving prognosis. CASE SUMMARY A 74-year-old man was admitted to the infectious disease department with > 10-d fever and 10-mo prior history of thoracic aortic stent grafting for thoracic aortic penetrating ulcers. Blood tests revealed elevated inflammatory indicators and anemia. Chest computed tomography (CT) showed postoperative changes of the aorta after endovascular stent graft implantation, pulmonary infection and pleural effusion. Pleural effusion tests showed empyema. After 1 wk of anti-infective treatment, temperature returned to normal and chest CT indicated improvement in pulmonary infection and reduction of pleural effusion. Esophageal endoscopy was performed because of epigastric discomfort, and showed a large ulcer with blood clot in the middle esophagus. However, on day 11, hematemesis and melena developed suddenly. Bleeding stopped temporarily after hemostatic treatment and bedside endoscopic hemostasis. Thoracic and abdominal aortic CT angiography confirmed AEF. Later that day, he suffered massive hemorrhage and hemorrhagic shock. Eventually, his family elected to discontinue treatment. CONCLUSION AEF should be strongly considered in patients with a history of aortic intervention who present with fever, especially with empyema.