The authors report the rare case of a patient with neurocutaneous vascular hamartomas mimicking Cobb syndrome. An 8-year-old boy was admitted to the authors' hospital with progressive urinary disturbance and upper back pain. Multiple skin nevi had been noted at the child's birth. Radiological examination revealed multiple cavernous angiomas in the spinal cord in the same metamere in which the skin nevi had been observed and also in the left cerebral hemisphere. His symptoms gradually improved without surgical intervention. Four years later he was readmitted because of a cerebral hemorrhage involving the left cerebral peduncle. Nonsurgical treatment was chosen because his symptoms promptly improved. To the best of the authors' knowledge, this is the first case of multiple cavernous angiomas in the brain and spinal cord associated with skin nevi. The authors discuss this clinical entity and the significance of the disease.