The Greens will write to the federal police seeking an investigation into links between the Mafia and political parties.
Slain gangland lawyer Joe Acquaro attended a 2008 fundraising lunch in Melbourne where then opposition leader Malcolm Turnbull was also a guest.
"The fact an opposition leader lunches with Mafia associates at a political party fundraiser should send shock waves through the election campaigns of all parties that are now inviting the corporate world to donate to their party and candidates for this election campaign," Greens senator Lee Rhiannon said on Monday.
The Melbourne lunch was organised by McMillan MP Russell Broadbent after Mr Turnbull became opposition leader, Fairfax Media and News Corp reported on Monday.
Also at the lunch were fruit mogul Tony Madafferi, brother of jailed drug trafficker Frank Madafferi, and Joe Mirabella, of Mirabella lighting.
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A spokesman for Mr Turnbull said he had attended the lunch, but "the prime minister does not recall the names of Mr Broadbent's guests".
Mr Broadbent told New Corp he "hadn't done anything wrong and resented the implication that he had by attending Liberal Party fundraisers".
Both Fairfax and News Corp say Mr Acquaro, who was shot dead in a Brunswick East street in March, had boasted about cultivating and donating to Liberal politicians.
It was also reported that Mr Acquaro had unsuccessfully lobbied for a government contract to supply environmentally friendly light bulbs when Mr Turnbull was environment minister in 2007.
