The guards told the ABC seven staff aged over 50 were not employed by MSS Security after the company took over the security contract at the university.

Federal Member for Bendigo Lisa Chesters said she would raise the "outrageous" issue of age discrimination in parliament.

"I think this is part of a wider issue," Ms Chesters said. "I think the contractor has treated the workers as second class citizens.

"I really, really feel for these security officers. They have worked hard to ensure the campus is safe and now they have been thrown on the scrap heap."

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A La Trobe University spokesperson said staffing decisions were the responsibility of the new provider, MSS Security.

"We require our suppliers and contractors to comply with Victorian and Commonwealth laws, including equal opportunity legislation," the spokesperson said.

But Ms Chesters said while La Trobe did not have a legal obligation to the security workers, the university did have a moral duty.

"At the end of the day, La Trobe is the client," she said. "They could have requested these workers' contracts are carried over into the new provider.

"There is a practice of that happening in other workplaces. La Trobe is just refusing to do that and saying it's not their problem."

One of the workers who spoke to the ABC has lodged an age discrimination complaint with the Victorian Equal Opportunity and Human Rights Commission.

A spokesperson for Victorian Minister for Industrial Relations Tim Pallas said the government would monitor the case.

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"No worker should ever be discriminated against - full stop - and there are laws in Victoria that ensure workers are protected," the spokesperson said.

"We're watching this matter closely and we'll await the outcome of the complaint raised with the Victorian Equal Opportunity and Human Rights Commission before considering our next steps.

"It would be inappropriate to comment while the matter is before the Commission."

United Workers Union national coordinator Damien Davie said the union would reach out to the affected workers.

"Unfortunately the security industry is an incredibly unregulated industry," he said. "Many of the workers face issues like this when there is a change in contract.

"Many companies do the right thing, but MSS Security is one company that will do whatever they can to save money."

MSS Security has been contacted for comment.

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