Questions have been asked about the Morrison government's planned review of the industrial relations system.

Labor frontbencher Katy Gallagher says the review may not be genuinely geared towards improving workers’ rights.

Prime Minister Scott Morrison has revealed plans for a review to be led by Industrial Relations Minister Christian Porter.

“Any changes in this area must be evidence-based, protect the rights and entitlements of workers and have clear gains for the economy and for working Australians,” he said.

Senator Gallagher said the Coalition's track record - including the Howard government's WorkChoices reforms and the Abbott government's royal commission into unions - shows they are biased.

“We've had a pretty blistering attack for the last six years whilst in government on unions, and a fair bit of union bashing going on,” she told Sky News.

“It's a bit hard for someone from my side of politics to sit there and listen to that and believe there is concern about workers' rights and conditions.

“History, form and practice would indicate that it's a pretty one-sided debate from the Coalition.”