We studied 96 families with Huntington's disease (HD). There were 396 deaths reported in 195 males and 201 females. Family history and clinical information about the deceased were collected and 40 suicides were found. Suicide occurred most frequently in the early or late stages of the disease; age at onset was slightly lower among those who committed suicide. Of the 40 subjects who committed suicide, 34 were male and 6 were female; this was not significantly different to the expected ratio based on suicide in the general population. Those who committed suicide had a smaller number of children than other HD patients. No significant relationship was shown between the sex of the affected parent and suicide. Four suicides occurred in hospital. Suicide among patients with HD is more common than in the general population. Knowledge about the high suicide risk in this disease is important for genetic counseling.