A pulmonary artery aneurysm is defined as pulmonary artery dilatation >4 cm. Pulmonary artery aneurysms are rare findings and are usually not associated with chest pain. This is the first report of a case of pulmonary artery aneurysm causing chest pain in a patient with Noonan’s syndrome. Chest X-ray showed cardiomegaly and a prominent main pulmonary artery segment and CT confirmed a pulmonary artery aneurysm with a pulmonary artery root measuring 5.6 cm. The patient underwent pulmonary valvuloplasty as well as pulmonary arterioplasty to repair the pulmonary artery aneurysm, and experienced subsequent relief of chest pain. In conclusion, pulmonary artery aneurysm is a rare complication in patients with Noonan’s syndrome and can be the cause of chest pain in such patients.