This study examined the prevalence of suicidal thoughts and associated factors in an elderly population. Data for 969 elderly subjects from a population-based study were used, and examinations by physicians, including psychiatric examination and informants' interview, were assessed. In total, 13.3% of the subjects had had suicidal thoughts during the last 2 weeks (10.8% fleetingly and 2.5% frequently). Of those who had had fleeting suicidal thoughts, 26.7% also had major depression, while 50% of those who had frequent suicidal thoughts were depressed. In addition, suicidal thoughts were associated with increased disability in daily living, institutionalization, visual problems and the use of psychotropic drugs. It is concluded that a careful psychiatric assessment is necessary when suicidal thoughts are expressed by an elderly person.