A 61 years old male patient having the complaint of angina pectoris underwent coronary angiography that revealed critical luminal stenosis at left anterior descending artery (LAD) and diagonal branch. Percutaneous transluminal coronary angioplasty was performed and sirolimus eluting stents (CYPHER; Johnson & Johnson - Cordis) 2.75 x10 mm and 2.75x10 mm were deployed respectively. One year after the procedure coronary angiography revealed coronary artery aneurysm (CAA) formation in diagonal branch and mild ectasia in LAD stent area. Last coronary angiography four years and three months after initial intervention showed multiple CAA at diagonal branch and LAD. This case report is an example of late formation of CAA by sirolimus-coated coronary stent. (C) 2009 Elsevier Inc. All rights reserved.