And one in three thinks that the oldest old should be allowed to take a pill to end their life if that's what they want to do, the study shows.
The findings are based on the survey responses of just under 2000 members of the general public in The Netherlands, where physician assisted suicide has been legal since 2002.
Doctors in The Netherlands can only legally help patients to die if the request is voluntary and has been well thought out, and if the patient is suffering unbearably with no prospect of improvement.
But the issue of whether it should be permissible for doctors to help elderly people who are not seriously ill, but who are simply tired of living, to die, has risen to the fore recently and is the subject of lively debate in Dutch society, say the authors, who wanted to gauge the level of public support for it.
They therefore canvassed a random sample of Dutch adults, aged 18 to 95, in 2009-10 about their attitudes to assisted dying for this group of people, using four statements and two vignettes - one of a healthy old person who is tired of living and the other of a younger person who is terminally ill.
Among the 1960 eligible respondents, over half (57%) agreed that everyone should have a right to euthanasia, and a similar proportion (53%) agreed that everyone has the right to determine their own life and death.
One in four (26%) agreed with the vignette in which a doctor helps an elderly person who is tired of living, to die. And a similar proportion (19%) said they would request this option themselves if they were in the same situation.
This compares with almost half of respondents who would ask a doctor to help them die if they were terminally ill.
And one in five (21%) agreed with the statement: 'In my opinion euthanasia should be allowed for persons who are tired of living without having a serious disease.' Just over half disagreed (52%), while one in four (25%) neither agreed nor disagreed.
A third (36%) also agreed that the oldest old should be able to get hold of pills that would enable them to die, if they so wished. And a further 30% were neutral.
Age and state of health had no bearing on acceptance of the right of elderly people tired of living to choose to die. But those who backed the option tended to be more highly educated, have no religious faith, and to consider it important to make their own end of life decisions. They also had less trust in doctors to comply with their wishes.
The authors say that the level of support for assisted dying among the elderly who are tired of living, as evidenced by the survey responses, is lower than that for people who are seriously ill.
But the responses nevertheless point to a "significant minority" in favour of the option, which suggests "that this topic should be taken seriously in the debate about end of life care and decision making," they conclude.