Segmental neurofibromatosis is a rare disorder characterized by cafe-au-lait spots and neurofibrobmas, or only neurofibroma, limited to one region of the body. Disease-associated systemic involvement is uncommon. Most patients with segmental neurofibromatosis do not have a family history of neurofibromatosis. In Korea, there have been 3 reported cases of segmental neurofibromatosis. None of them had caf6-au-fait spots, systemic involvement, or family history. This report describes a case of segmental neurofibromatosis in a 25-year-old woman who had Becker's nevus-like cafe-au-lait spots and this was linked to the presence of Fanconi's syndrome in a second degree relative of the patient.