Aortobronchial fistula presenting as massive haemoptysis is a rapidly fatal process if not promptly diagnosed and repaired. It's an unusual complication of thoracic aneurysm. We report the case of a 61-year-old woman with rupture of a thoracic aortic infectious aneurysm secondary to an Escherichia coli infection. Aortobronchial fistula diagnosis should be considered in patients who have minor or major haemoptysis and correct diagnostic procedures should be performed early. An aggressive surgical approach is often necessary.