The aim of the study was to further describe the characteristics of drug-dependent patients who attempt suicide. Thus, 449 drug-dependent patients were interviewed about whether or not they had ever attempted suicide and about their family history of suicidal behavior. Patients completed the Childhood Trauma Questionnaire and the Eysenck Personality Questionnaire, and were interviewed with the Addiction Severity Index (ASI). It was found that patients who had attempted suicide (N=175) were significantly younger than patients who had never attempted suicide (N=274). Significantly more of the patients who had attempted suicide were female; had a family history of suicide; and had a lifetime history of major depression, of having received antidepressant medication, and of alcoholism. Also, patients who had attempted suicide had significantly higher scores for childhood trauma, psychoticism, neuroticism and introversion, as well as higher ASI psychiatric composite scores. These results suggest that social, personality, family, developmental and psychiatric risk factors may predispose to suicidal behavior in drug-dependent individuals.