Two cases of vascular malformations coexisting with other congenital defects of the central nervous system (CNS) are presented here. The first patient was a 14-year-old girl mentally retarded who demonstrated seizures and balance disturbances with onset in early infancy. The neuropathological examination revealed vascular malformations in the pons, diastematomyelia (triple central canal) in the sacral spinal cord and palleocerebellar granular layer dysplasia. The second patient was a 10-year-old boy hospitalized because of purulent dermatitis who suddenly developed recurrent generalized and focal motor seizures. The neuropathological examination disclosed multiple capillary teleangiectases with focal anomalies within cerebral cortex of the frontal and parietal lobes. The relations between several developmental anomalies in the CNS and possible causal relation between such malformations are discussed.