The association of parity and infant mortality was studied using linked birth-death files for 46,985 infants born to 11- to 19-year-old Minnesota residents between 1980 and 1988. Compared with infants of primiparas, infants of multiparas were at twice the risk for infant and postneonatal death but at no increased risk for neonatal death. They were also at two to three times the risk for deaths due to accidents, infections, and sudden infant death syndrome. The higher sociodemographic disadvantage and poorer prenatal care of multiparas did not explain the excess infant mortality risk that was concentrated in causes of death that are potentially preventable through primary care and parent education.