Opposition Leader Tim Nicholls has acknowledged past mistakes under the Liberal National Party, but promises they won't be repeated if Queenslanders elect him to office.

Addressing the LNP's campaign launch in Brisbane on Sunday, Mr Nicholls said he would not let voters down if he became premier at next Saturday's decider.

"I have said it and I mean it, we made mistakes in the past that a future LNP government would never make again," he said, standing before his family, party faithful, Prime Minister Malcolm Turnbull and federal members George Brandis and Peter Dutton.

Mr Nicholls repeated pledges to cut payroll tax for small businesses across the state, re-introducing the Royalties for Regions program, a $20 million package for mature-age jobseekers and a strategy to cut power prices, plans he is yet to say how he will fund.

He also lashed out at the state Labor government, claiming it had not done enough to bring down power prices or deliver key infrastructure projects.

Earlier, Mr Turnbull said Queenslanders had a "clear choice" to elect the LNP, while former premier Campbell Newman dished out some campaign advice ahead of the poll.

"One of the things that Tim needs to do this campaign is differentiate himself from my government and that's fair and reasonable, he's his own man," Mr Newman told Sky News.

"He will, if he becomes the premier, have his own style of leadership, and everyone will respect that, but fundamentally Tim Nicholls has the goods.

"He was a very effective treasurer, he knows what the state needs."

As treasurer, Mr Nicholls slashed thousands of public sector jobs and proposed to sell off state assets, unpopular decisions that led to the party's dramatic dump from parliament in 2015.

Mr Nicholls has been criticised by Labor throughout the campaign, with the government taking aim over his former portfolio and position as Mr Newman's right-hand man.