South Australia is committed to lifting workforce skills and training to meet the needs of some $80 billion of big development projects in the state, Treasurer Jack Snelling says.

The South Australian Training and Skills Commission has estimated there will be over 160,000 job openings in the state over the next five years, with almost half of them being new jobs, the treasurer said on Tuesday.

"The ongoing challenge for government is to make sure we have the right numberof skilled people in South Australia ready to take those jobs," he told an Australian Industry Group briefing in Adelaide.

The treasurer said the government's Skills for All reforms would set future directions for the vocational education and training system, which should address this need.

Snelling said the government also needed to focus on small business, with a recent survey showing a significant drop in business confidence across the nation.

"With consumers cautiously looking to save their money rather than spend it, businesses are no doubt doing it tough," he said.

He told the forum SA's record spending on infrastructure should support business and industry.

"Whether it's the new Royal Adelaide Hospital, right next door here at the Adelaide Oval or the Southern Expressway duplication, just to name a few, these investments will keep the economy moving in difficult times," he said.

Through these infrastructure projects and public and private investment, the South Australian economy is at an unprecedented level with about $80 billion worth of major developments are underway or planned, he said.