Behçet disease (BD) is a systemic disorder caused by underlying vasculitis of unknown origin. In this paper we present a case of a 26-year-old male patient who was admitted at our Emergency Department with massive haemoptysis due to pulmonary arterial involvement in BD. The discussion of this case helps to remember that BD is the main cause of aneurysm of the pulmonary arteries and a cause of haemoptysis in young patients. Therefore, the radiologist plays a key role in the identification of intrathoracic alterations with chest computed tomography. The knowledge of clinical manifestations and distinctive elements of BD allow an accurate diagnosis and let the patient to be directed towards an appropriate treatment, in order to avoid the onset of life-threatening complications.