Suicide in the elderly is one of the major issues in the field of psychiatry. In Japan, the suicide rate among aged persons is very high, and the proportion of suicides among those aged 65 years and older to all suicides (27.6 % in 2010) is higher than that of those aged 65 years and older to the total population (23.1% in 2010). It is revealed that the vast majority of the elderly suicides suffered from depression at the time of suicide. Elderly people tend to have many loss experiences and also to have their executive function declined. Such tendencies might contribute, psychologically and biologically, to high lethality of their suicidal behavior. Attention should be paid to dementia, in particular its early stage. It is important for clinicians to ask depressed patients about death wishes and help suicidal patients seek for social support as well as psychiatric treatment.