South Australia has called for more people to become organ donors as the number waiting for a kidney transplant rises.

The waiting list for kidney transplants in South Australia has climbed to 80, prompting calls for more people to become organ donors.

Health Minister Jack Snelling says the list is at its highest since 2008 when 58 people needed transplants.

The minister has encouraged people to talk to their family and friends to make their views known about organ and tissue donation and to sign up to the Australian Organ Donor Register.

"The passing of a loved one is always a stressful and emotional time for the family members who are left behind," Mr Snelling said.

"During this time it is often very difficult to carefully consider the option of organ and tissue donation."

Research from DonateLife shows that about 60 per cent of Australian families provide consent for organ and tissue donation, rising to about 80 per cent when families are aware of the wishes of their loved ones.

Director of kidney transplantation at the Royal Adelaide Hospital, Toby Coates, says the hospital has only performed 15 transplants so far this year compared with 34 at the same time in 2014.

In 2014 South Australia also recorded the highest rate of organ donation of any state, with a rate of 21.4 per million people, well above the national figure of 16.1
Professor Coates says just one organ and tissue donor can help 10 or more people who are in need.