A 24-year-old man presented clinically confirmed Behcet's disease. He developed thoracic pain accompanied by hemoptyses as a result of thromboses and aneurysm formation in the pulmonary artery. The presence of these aneurysms was suggested by perihilar images on standard radiography, and confirmed by pulmonary arteriography findings and results of histological examination of the operative specimen. Radiological and anatomical evidence of the presence of bronchial endarteritis lesions was also obtained.