Whether a family history of suicide (FHS) might increase the risk for suicidal behavior through an effect on personality was examined. Patients with a first or second-degree relative who had committed suicide were compared with matched patients with a negative FHS for their scores on the Eysenck Personality Questionnaire (EPQ). The trend for a difference on EPQ neuroticism scores between the total groups became significant when subgroups of FHS positive and negative patients, who had no personal history of attempting suicide, were compared. Further studies of the relationship of a family history of suicide to personality are needed in other populations and incorporating biologic measures.