OBJECTIVE: To evaluate CT and MRI images in the diagnosis of corpus callosum dysplasia. METHODS: The CT and MRI findings in 16 pediatric and adult cases with corpus callosum dysplasia were reviewed. RESULTS: CT and MRI diagnostic criteria of corpus callosum dysplasia were: ①separation of the frontal horns of the lateral ventricles and interventricular foramina; ②nearly parallel separation of the bodies of the lateral ventricles; ③enlarged occipital horns of the lateral ventricles; ④dilatation and anterior displacement of the third ventricle; ⑤abnormal proximity of interhemispheric fissure to the anterior part of the third ventricle. CONCLUSIONS: Correct diagnosis of corpus callosum dysplasia could be made on the basis of CT and MRI characteristics, but MRI might directly reveal the developmental abnormality of the corpus callosum on sagital scans.