The Opposition has accused the State Government of wasting taxpayers' money, after a report revealed a 40 per cent hike in Treasury consultant fees.

The Department of Treasury's annual report, tabled in Parliament this week, shows the agency spent $17 million on consultant fees last financial year.

The department spent $12 million in the previous financial year.

The Shadow Treasurer Ben Wyatt says the money would have been better spent on keeping workers in the public sector.

"This is a typical trajectory of Liberal governments, they look to sack public servants while ratcheting up in the millions of dollars in the amount they spend on private consultants," he said.

"It's not an efficient way of spending taxpayers' money."

The Treasurer Troy Buswell has been contacted for comment.