A former associate of WA One Nation senator Rod Culleton is challenging his eligibility for Parliament in the Court of Disputed Returns.

Key points: Rod Culleton elected as One Nation senator for WA

Rod Culleton elected as One Nation senator for WA Former associates have lodged an application challenging his eligibilty

Former associates have lodged an application challenging his eligibilty Rod Culleton has been director of three companies that have gone into administration owing more than $11 million

The petition lodged with the High Court claims the Senator is ineligible to nominate as a candidate because at the time of nomination, he was convicted and awaiting sentence for a crime carrying a penalty of more than 12 months in jail.

That conviction, over a larceny charge in New South Wales, took place in Senator Culleton's absence and was annulled earlier this month to be re-heard at a later date.

However, the petitioner, former associate Bruce Bell, said he is confident his application will be successful.

"It's perfectly clear under Section 44, he nominated and on a sworn form, whether it was knowingly or otherwise ... you say 'you're eligible', he wasn't, because he was under pain of sentence for a crime that potentially exceeded 12 months jail," Mr Bell told 7.30.

When contacted by 7.30, Senator Culleton said he had not heard about the petition against his eligibility but said, "'I have no concern whatsoever, why should I?"

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It remains to be seen whether the petition will be accepted by the Court.

Former associate, Bruce Bell, is challenging Rod Culleton's right to sit in the senate.

Mr Bell and another former colleague, Frank Bertola, met Senator Culleton when they were fighting the banks alongside each other, now their dispute is against him, and the Senator has taken out a restraining order against the pair.

Along with Senator Culleton, Mr Bertola served as a director of horse feed company Deqmo Pty Ltd.

Then director Senator Culleton placed Deqmo in external administration earlier this month, with creditors' claims totalling $4.8 million.

The Supreme Court on Thursday ordered that company be wound up in insolvency.

Wheatbelt locals 'disgusted' by former farmer's election

The One Nation senator has served as director of three companies that have gone into administration, with creditors claiming they were owed a combined total of more than $11 million.

One creditor from former wool-buying business Culletons Pty Ltd, Wagin Shire President Phil Blight, said it had given him a bad name in the region.

"My 40th birthday present was a call from the administrators saying this company had gone into administration, owed us money, owed a lot of people in the area money," he said.

"[There was] something around 100, 120 wool growers I think it was at the time plus their was a lot of small businesses like mechanics, retail outlets, motor vehicle franchises, that sort of thing."

Wagin Shire President Phil Blight says locals were "disgusted" when Rod Culleton was elected to the senate ( Lauren Day )

Senator Culleton declined 7.30's request for an interview but said he was "a very good businessman" who had merely found himself captain of several ships in rough waters.

Mr Blight said he was "disgusted" when Senator Culleton was voted in.

"All of those companies have failed under Rodney's directorship so it's hard to see at the pointy end of setting the budget for Australia that this fellow knows what he's doing," he said.

Senator Culleton is also being pursued by former Wesfarmers director Dick Lester for an order to pay $205,000, which Senator Culleton is appealing.

Senator Culleton said he failed to see the relevance of his past financial dealings.

He is also suing 18 people for defamation over Facebook comments about a 60 Minutes story he was featured in about farm foreclosures.