Three cases of infantile neuroaxonal dystrophy diagnosed by conjunctival biopsy are reported. Some axons of the conjunctival nerves showed aggregates of tubular and membranous structures identical to the spheroids of the CNS. The visualization of these structures is the only diagnostic tool in this disease of unknown metabolic basis. Conjunctival biopsy which is ease to perform is the preferential technique for the diagnosis òf this disease. Clinically, the intense hypotonia with pyramidal tract signs, the absence of seizures, the cerebellar atrophy observed at the computerized tomography suggest strongly the diagnosis of infantile neuroaxonal dystrophy.