We present a rare case of unilateral multiple large thrombosed pulmonary artery aneurysms that occurred in the course of chronic pulmonary thromboembolism in a 51-year-old man. Chest radiography showed multiple rounded opacities in the right hilar and parahilar regions. CT scans showed marked aneurysmal dilatation of the segmental and lobar branches of the right pulmonary artery containing large thrombi. This pattern of pulmonary artery aneurysms has not been previously reported.