The CFMEU claims foreign workers are stealing mining jobs from locals and preventing the wealth of the boom from spreading to the wider community.
As part of a pre-election advertising blitz the Construction, Forestry, Mining and Energy Union has reignited fears over imported labour, which it says accounts for too many jobs in the mining sector.
CFMEU national president Tony Maher told ABC News regulation for imported labour was too soft and foreigners were also being favoured for supply and manufacturing services.
“There are lots of Australians who can't get employment in the mining industry and that's because there's too much easy access to imported labour and the other problem is that the big mining projects aren't required to use local content,” he said.
But Australian Mines and Metals Association executive director Scott Barklamb said importing workers was difficult and expensive for mining companies, and was only used on special occasions.
“It's a myth to say that business is consciously being restructured or structured deliberately to use overseas labour,” he said.
Earlier this year the WA Government said its Industry Facilitation and Support Program had awarded millions of dollars in contracts to local suppliers working for mining companies.