The first analysis of multiple cause-of-death data for Huntington's disease in the United States was performed, using data from the National Center for Health Statistics for the period 1971 and 1973 through 1978. The overall mortality rate was 2.27 per million population per year, approximately 80% higher than the corresponding rate for deaths in which Huntington's disease was listed as the underlying cause of death. Age-specific mortality rates peaked around age 60. Rates were similar for both sexes, and higher in whites than nonwhites. Age-adjusted rates were similar for United States whites and reported values from the Scandinavian countries. The leading causes of death were pneumonia and heart disease. Other common causes of death were nutritional deficiencies; mental disorders; cerebrovascular disorders; and accidents, poisonings, and violence. Suicide was rarely reported.