A total of 209 consecutive neonate and infant autopsies were reviewed with special attention to papillary muscle necrosis (PMN) of the heart. Associated major pathological findings were analysed for the evaluation of significant pathological accompaniments of PMN. PMN was found in 52 cases among 171(30.4%) neonates and major pathological accompaniments were bronchopneumonia, hyaline membrane disease, hypoxic neuronal change, sepsis, subarachnoid hemorrhage, disseminated intravascular coagulation (DIC) and acute tubular necrosis, among which hypoxic neuronal change and ATN had a statistically significant higher incidence when compared with the control group. (p < 0.005). PMN was found in 13 cases among 38(34.2%) infants and accompaniments were congenital heart disease, sepsis, bronchopneumonia, DIC and hypoxic neuronal change, all of which showed no difference from the control group in incidence. The results imply that PMN is a kind of organ damage in stressed subjects regardless of age, that it is not a special form of myocardial injury in any specific age group including the newborn period, and is possibly of different pathogenesis and significance.