Delayed postanoxic encephalopathy causes relapse of cognitive impairment and movement deterioration in a few weeks after clinically complete recovery from initial anoxic or hypoxic insult. Delayed postanoxic encephalopathy is a rare condition, and its clinical symptoms are characterized by abulia, apathy, akinesia, confusion, agitation, parkinso-nism, chorea, dystonia and/or progressive neurologic deficits. We reported two distinguished cases caused by carbon monoxide intoxication and mixed respiratory and metabolic lactic acidosis. (J Korean Acad Rehab Med 2006; 30: 522-527)