Background: Behcet's disease is a chronic multisystemic vasculitis affecting vessels of different sizes in various organs. Thoracic manifestations of the disease show a wide spectrum involving a variety of anatomic structures within the chest. However, pulmonary artery involvement is a typical manifestation of the disease that contributes significantly to mortality in patients. The study aimed to analyze CT features of thoracic manifestations, particularly pulmonary artery involvement, and to quantitatively assess bronchial arteries in Behcet's disease. Methods: Patients with Behcet's disease who underwent CT scans for suspected thoracic involvement between 2010 and 2018 were included. CT findings of 52 patients were retrospectively analyzed for thoracic manifestations of the disease. Bronchial arteries were assessed regarding diameter in patients with/without pulmonary artery involvement. The pulmonary symptoms were noted. Results: Of the 52 patients, 67% had thoracic manifestations including pulmonary artery involvement, parenchymal changes, superior vena cava thrombosis, and intracardiac thrombus. Pulmonary artery involvement was observed in 50% of the cohort. Peripheral pulmonary arteries (77%) were the most commonly affected branches, followed by lobar (42%) and central (35%) pulmonary arteries. Other thoracic findings were significantly correlated with pulmonary artery involvement (p<0.05). Compared to patients without pulmonary artery involvement, those with pulmonary artery involvement had a higher bronchial artery diameter (p<0.05) and occurrence rate of dilated bronchial arteries. Conclusion: Involvement of peripheral pulmonary arteries is frequently encountered in Behcet's disease and it can resemble pulmonary nodules. Dilated bronchial arteries, which can be observed in cases of pulmonary artery involvement, should be considered in patients with hemoptysis.