Two patients with congenital nevus of Ota developed intracranial malignant melanocytic tumors. One had a localized tumor that resembled a melanocytoma, but the other had a more highly malignant tumor that diffusely seeded the leptomeninges. There are 10 prior cases in the world literature. These cases are contrasted with the other disorders in which melanotic skin lesions are associated with CNS melanocytic tumors, including neurocutaneous melanosis, cellular blue nevus, and metastatic malignant melanoma. Each disorder tends to involve particular sites of the CNS. The nevus of Ota can be considered a neurocristopathy and, rarely, may give rise to malignant CNS lesions.