Kawasaki disease (KD) is a common acute vasculitis in pediatric population that usually involves small and middle-sized arteries, commonly coronary arteries. Although the incidence and natural course of coronary aneurysms after KD are well documented, related reports on peripheral arterial and aortic aneurysms are scarce. We report an original case of a giant aortic aneurysm involving the horizontal part of aortic arch in a 28 months- old patient diagnosed with Kawasaki Disease. This complication was managed by steroids therapy in the beginning than surgery was indicated because of mechanical complication and risk of rupture.