Wernicke encephalopathy is a neurologic disorder that results from thiamine deficiency. It is associated with a classic triad of symptoms consisting of ataxia, ocular motor cranial neuropathies, and changes in consciousness. We report 3 cases of Wernicke encephalopathy in which MR imaging, including diffusion-weighted imaging, was performed at the onset and during follow-up. MR imaging findings were correlated with the clinical status of both the acute and chronic stage of Wernicke encephalopathy.