A 57-year old man with chronic alcoholism presented with apraxia of speech and disturbance of consciousness. He had a history of gastrectomy and had been drinking alcohol. The symptoms improved with administration of thiamine, but he later developed diarrhea and delirium, and died approximately 40 days after the onset. Autopsy findings were consistent with Wernicke's encephalopathy and pellagra encephalopathy. Furthermore, laminar cortical necrosis with vacuoles and astrocytosis was found in the second and third layers of the bilateral frontal cortices, suggesting Morel's laminar sclerosis. The lesions were mainly located in the bilateral primary motor cortices. Involvement of the lower part of the left primary motor cortex may be associated with apraxia of speech in our case.