We report on a 16-month-old boy who presented with truncal ataxia and intermittent nystagmus. Magnetic resonance imaging (MRI) at 19 months showed a T (2)-hyperintensity of the splenium and the genu of the corpus callosum with extension into the adjacent frontal white matter. Diffusion tensor imaging (DTI) revealed a corresponding area of restricted diffusion, suggesting cytotoxic oedema. The extent and localisation of the signal abnormalities mimic tissue injury as seen in Marchiafava-Bignami disease (MBD). Metabolic investigations were normal. Follow-up imaging at 24 months showed a similar T (2)-hyperintensity of the corpus callosum and white matter while on DTI the cytotoxic oedema had resolved. Clinically a remaining truncal and gait ataxia, clumsiness and a developmental delay is seen. Goal of this case report is (a) to present a rare case of Marchiafava-Bignami-like injury of the corpus callosum in an infant and (b) to discuss the neuroradiological imaging findings including MRI and DTI.