Marchiafava-Bignami disease (MBD) is characterized by demyelination and necrosis of corpus callosum encountered in chronic alcoholic patients. Etiology is the deficiency of vitamin B complex. Magnetic resonance imaging (MRI) in MBD typically reveals focal lesions of high T2 and FLAIR signal intensity in the corpus callosum. We here present a 42-year-old male alcoholic diagnosed as MBD on the basis of MRI and diffusion-weighted imaging (DWI) features. The patient totally recovered following appropriate vitamin B complex replacement therapy, despite reduced diffusion in the initial setting. This case report emphasizes on the important role played by MRI and DWI in the early diagnosis and follow-up of this potentially fatal disease.