Williams-Beuren syndrome is a multisystem genetic disorder caused by hemizygous deletion on chromosome 7q11.23, encompassing about 28 genes including the elastin gene, ELN. Cardiovascular abnormalities are frequent and are related to elastin insufficiency. These abnormalities include supravalvular aortic stenosis (SVAS) in 70% of case, pulmonic valve stenosis, and renal artery stenosis. Definitive therapy for supravalvar aortic stenosis consists of surgical correction of the arteriopathies. Outcomes after surgical correction of SVAS depend on the extent of the arteriopathy and the presence of other associated lesions. We present a case of a 4-year-old boy, with Williams - Beuren syndrome with an SVAS. The patient was assessed with computerized tomography angiography to determine the extent of the aortopathy before surgical intervention.