Public hospital doctors in South Australia have walked off the job amid a dispute with the state government over pay and conditions.

Their union, the Salaried Medical Officers Association, says doctors are being asked to accept a 1.5 per cent wage increase but no improvement to conditions.

The union says other medical staff, including nurses and paramedics, have been granted 2.5 per cent pay increases and improved conditions.

“I have met with members twice over the last month and they have unequivocally rejected this offer,” Association president Dr Laura Willington said.

The stop work meeting was set up so as not to impact on patient safety, with appropriate cover organised for doctors participating.

Elective surgeries at several hospitals were cancelled in advance, but emergency departments were unaffected.

Health Minister Peter Malinauskas said the government knew the industrial action was coming.

“Having known that this was coming, meant that it gave us the capacity to not put in place elective surgeries today that would have otherwise been the case,” Mr Malinauskas told the ABC.

Mr Malinauskas said the government had shown goodwill in the negotiations, having met three times with the union since he took over the portfolio.

“My job now is to make sure that we continue to negotiate to see if we can't get a resolution that is in the interests of the health system generally,” he said.

Dr Willington said the union had been in negotiations for over 18 months, and wanted resolution soon.