Private training college Vocation has been forced to recall more than 1,000 of its qualifications including hundreds in child care and aged care after Victorian regulators found the courses were sub-standard.

Almost 200 students who completed a Certificate III in Child Care, 250 students who completed a Certificate III in Aged Care, and 383 students with a double qualification of business studies will have to hand back their qualifications and inform their employers.

A total of 832 students, who all studied with Vocation in Melbourne between January until June last year, are affected.

Graduate Tracey Martin just learnt she would have to hand back her Certificate III in Aged Care.

She is employed at a nursing home and is uncertain about what re-training she will now need.

"I've been working in the industry for the last seven months," she said.

"I really don't know what it is that I need to redo, It could be a few hours' work, it could be a month or so, I've got no idea and they're not telling us."

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This latest audit by the Victorian Registration and Qualification Authority (VRQA) follows an investigation last year which found about 6,000 students had studied sub-standard courses.

More than 3,500 qualifications were recalled, and Vocation was forced to repay $19.6 million in state government funding.

The Victorian Education Department said it was still in discussions with Vocation about the return of government funding for "qualifications recalled in April 2015" but the ABC understands the bill could be as high as $2.5 million.

Vocation was the first private college to list on the Australian Stock Exchange, and is yet to inform the market about this latest recall.

This morning it was trading at 16 cents per share, well down from its high of $3.30 in September 2014.

In a statement Vocation said: "The company announced to ASX on March 2, 2015, that there remained a number of regulatory audits either in progress, or with outcomes pending, and likely to be concluded in the near term.

"The company is still in discussions with the regulator regarding how much money will be repaid."

A spokesman for the Victorian Department of Education and Training said eight early childhood services and four aged care homes had indicated they employ staff affected by the recall of qualifications.

"The Department is supporting students who wish to continue working in [these] sectors by arranging for skills assessments to help identify what further training they will need to regain their qualification," the spokesperson said.

"This retraining is at no cost [to] the student."

The Australian Education Union Deputy federal secretary Pat Forward said Vocation had lost its right to receive any further Victorian government funding.

"The evidence is there of problems within that company and I think it's a question that has to be thrown back onto the regulator," Mr Forward said.

"Can [the department] with any confidence hold their hands on their hearts and say students who enrol in Vocation are going to get the quality of delivery and service they require?"

Law firm Maurice Blackburn is pursuing a class action against Vocation. It will allege the company misled the stock market by failing to notify investors that it was repaying almost $20 million to the department.

Support and advice for students and any employers affected by the recall is available by calling the Victorian Government Call Centre on 1300 842 754.