We reviewed national mortality data for 1973 through 1983 to assess the importance of diarrheal diseases as a cause of preventable childhood death in the United States. An average of 500 children aged 1 month to 4 years died each year with diarrhea reported as the cause of death. These diarrheal deaths were most common among children who were younger than 1 year of age, black, and living in the South, and were most common during the winter. In Mississippi, review of fatal cases of diarrhea identified maternal factors--black race, young age, unmarried status, low level of education, and little prenatal care--to be most associated with diarrheal death in the child. Fifty percent of these deaths occurred after a child had reached a medical facility. Our findings suggest that diarrheal deaths may be preventable and that targeted interventions could contribute to improved child survival in the United States.