Three sisters with benign intracranial hypertension are reported. This is the first documentation of benign intracranial hypertension in three family members. Obesity is a striking feature in these patients as well as five of the six previously reported patients with familial benign intracranial hypertension. Pregnancy and chronic dysfunctional uterine bleeding, well known predisposing factors in this syndrome when it occurs sporadically, were present in two of the sisters. A familial metabolic defect may be responsible for the intracranial hypertension in these patients.