The perinatal mortality rates and causes of deaths in our hospital within the three 5-year periods (1955-1959, 1976-1980, 1981-1985) were reported as well as the total number of births (16 846), deaths (457), and autopsies (393, autopsy rate 85.9%). The perinatal mortality for the three 5-year period was 44.5%, 23.8%, and 17.2% respectively; it declined more significantly in 1981-1985 than in 1976-1980. Anoxia was the first cause of death for the three 5-year periods. Other causes in sequence in 1955-1959 were traumatic intracranial hemorrhage and pulmonary disease, in 1976-1980 malformation and pulmonary disease, and in 1981-1985 anoxia, pulmonary disease and hyaline membrane disease. Result suggest that accurate analysis of causes of deaths depends on meticulous systematic fetal and neonatal autopsy, including macerated fetuses, extensive discussion by pathologists, obstetricians and neonatalogists, and indispensable placental examination.