South Australia has appointed a top-ranking health expert as its first mental health commissioner, but the position may not last.

Dr Stephen Christley - the state's chief health officer - says his new job as mental health commissioner is just an interim one until the perfect permanent commissioner can be found.

Dr Christley was given the job to fulfil a Government pre-election pledge to spend $9 million setting up an independent mental health commission.

Mental Health Minister Jack Snelling said the hunt is on for the best and brightest.

“We'll be advertising and undertaking an extensive search for an ongoing commissioner,” he told reporters.

“We'll be looking around the country for the best and brightest to lead the commission over the next few years.

“I encourage anyone who has an interest in leading such an important area to apply.”

Mr Snelling said that for now, Dr Christley was had all the credentials to hold the role.

“Dr Christley has a wealth of knowledge and expertise in contributing to the health and wellbeing of South Australians,” he said.

“A key priority of the commission will be to lead the development of a five-year mental health plan, in consultation with key groups such as service providers and those with [experience of] mental illness.

“It will also monitor and provide advice about government programs and services for those with mental illness — such as education, employment and housing.”

Dr Christley said he was eager to tackle the challenges ahead.

“With one in five South Australians experiencing a mental illness, it is an issue close to many people's hearts,” he said.

“I'm honoured to take on the role of interim mental health commissioner and further build a strong strategic direction for mental health in South Australia.”