A 15-year-old girl was admitted because of an acute onset of facial palsy and right hemiparesis. The patient had a history of moderate mental retardation and developmental delay. On admission, her vital signs were stable, except for high blood pressure. Magnetic resonance imaging demonstrated an infarct involving the left internal capsule and putamen. Because of the patient's young age, an extensive stroke survey was performed. Williams-Beuren syndrome was finally confirmed by fluorescent in situ hybridization. Compared with the previously reported cases, no evidence of cerebral arterial stenosis or cardiac abnormalities was found by noninvasive imaging techniques. Because Williams-Beuren syndrome is a complex, multiple congenital anomaly syndrome with prominent cardiovascular features, regular assessment and antihypertensive treatment are necessary to minimize the lifelong cardiovascular risk in patients with this syndrome.