The Australian Sex Party says Family First approached it about doing a preference deal for the federal election.

A spokesman for Family First Senator Steve Fielding has confirmed a staff member met the Sex Party but also met all other parties to discuss policy and candidates for the election.

Family First federal chairman Bob Day said no preference offer was made and that raising the issue was part of a Sex Party campaign to discredit Family First.

Mr Day said Family First would never contemplate a deal with the Sex Party.

"One of their key aims was to stop Family First and this story's obviously part of that attempt to discredit," he said.

"But I can assure you that it is completely false. We would not, have not, and would never contemplate such an arrangement."

The Sex Party's president, Fiona Patten, remains adamant approaches were made.

She says they were made by telephone, email and in person at Melbourne Airport.

"I was a bit stunned they would be approaching us and I couldn't see that there was anything we had in common," she said.

Ms Patten supplied the ABC with copies of emails.

She said the Australian Sex Party would be urging voters to put Family First last among their preferences.

Senator Fielding's office said meetings were routinely held with other political groups.

It said Family First was keen to know where the Sex Party was directing its preferences so it would not inadvertently favour the Sex Party.