Phosgene (COCl2) is a colorless oxidant gas which is heavier than air and the lethal exposure dose (LC50) in humans is 500 ppm/min. This gas was originally manufactured as an agent for chemical warfare during World War I and there had been a great deal of studies on phosgene poisoning during the early years of industrial use. It is still widely used in the synthesis of chemicals and plastics. In the modern era, however, phosgene poisoning is relatively uncommon except in accidental exposures. In Korea, there has been no report about lung injury from phosgene inhalation. We present a clinical experience with six patients accidentally exposed to phosgene.