A 50-year-old man was referred to our hospital because of persistent atypical chest pain. His past medical history was remarkable for a non ST elevation myocardial infarction, treated five months previously with PCI on the right coronary artery. Two months later, for chest pain, he underwent coronary angiography that showed a right coronary artery with slight ectasia near the stent. Five months later for the persistence of atypical chest pain he came to our clinic. Chest CT showed a 31.5 mm hematoma of the right coronary artery. Coronary angiography revealed a giant aneurysm, proximal to the stent. In the light of rapid growth of aneurysm, the risk of rupture and symptoms, we decided to treat the aneurysm with covered stents. The patient underwent successful PCI with regression of symptoms.