A female patient, who was diagnosed with Leigh syndrome at 15 months of age, developed fulminating severe hypertension and died at 8 years of age. Hypertension has not been reported as an important clinical symptom in Leigh syndrome. Laboratory findings indicated that it was not associated with endocrinopathic diseases such as pheochromocytoma and aldosteronism, or renal diseases. Brain MRI scan showed symmetrical lesions in the basal ganglia and medulla oblongata including the nucleus tractus solitarius. This nucleus is known to play an important role in maintaining blood pressure. Since the medulla oblongata is a vulnerable site, potential development of hypertension should be taken into consideration when managing Leigh syndrome.