This paper describes infant mortality, leading causes of death, and some associated factors among the Han, the Miao, the Bouyei and other minority nationalities in three counties of the middle part of Guizhou Province, China. The results showed that the overall infant mortality rate (IMR) in these areas was 125.7 per 1000 live births during 1985-1987. There existed a great disparity in IMR among different nationalities. The rate was 103.1 (Han), 148.8 (Miao), 161.2 (Bouyei) and 145.0 (other ethnic groups) per 1000 live births, respectively. The five leading causes of death in infants were respiratory diseases, neonatal tetanus, birth asphyxia, infectious diseases and diarrhoea. These causes of death combined resulted in an IMR of 104.1 per 1000 live births. However, these diseases varied in importance for infants of different nationalities. We considered the relationship between infant death and maternal and child health care. The location of birth, the kinds of birth attendants and utilization of health facilities might be associated with differentials of infant mortality among these nationalities. Maternal education was associated with infant survival, but it might not be the only factor in decreasing or eliminating the differential of IMR among various nationalities. Based upon the findings, it is urgent to improve maternal and child health care and investigate further cultural and sociological factors among various nationalities.