The influence of breech and vertex delivery on intrapartum fetal and neonatal mortality was studied in 8,863 infants delivered at Kurashiki Central Hospital Perinatal Center. The rate of mortality was studied in cases without fatal congenital anomalies. The frequency of congenital anomaly was also studied in 8,863 infants delivered by breech and vertex presentation. Infants were divided into five groups according to their birth weight: 99g or less, 1,000-1,499g, 1,500-1,999g, 2,000-2,499g and 2,500g or more. Infants were also grouped into four by gestational age: 24-27 weeks, 28-31 weeks, 32-36 weeks and 37 weeks or more. The total infant mortality rate was 4.9% in breech delivery, and 0.5% in vertex delivery, respectively. This difference was statistically significant. The rate of major congenital anomaly in breech delivery was significantly higher than in vertex delivery. The rate of premature deliveries in breech presentation was also significantly higher than in vertex delivery. The rate of mortality in the group weighing 1,000-1,499g was 50.0% in breech delivery, and 17.6% in vertex delivery, respectively. This difference was statistically significant. The rate of mortality in the group delivered at 28-31 weeks gestational age was 62.5% in breech delivery, and 15.4% in vertex delivery, respectively (statistically significant). The rate of severe neonatal asphyxia in infants delivered at 28-31 weeks of gestational age was significantly higher in breech delivery than in vertex delivery.