Jetstar is being taken to court for allegedly allowing cabin crew recruited from Thailand to be paid about half the rate of the budget airline's Australian staff.
The Fair Work Ombudsman claims Thai crew working on Jetstar's domestic routes are owed thousands of dollars in back-pay.
The ombudsman will urge the Federal Court to stop the alleged underpayments at a hearing on August 17.
"While litigation commenced today involves just eight foreign workers, subject to the findings of the court, the Fair Work Ombudsman may take further action for up to 300 international cabin crew rostered across Jetstar's domestic routes," the ombudsman said in a statement.
Along with Jetstar, the ombudsman's case involves two Asian recruitment firms part-owned by Jetstar's parent, Qantas.
Valuair Ltd and Thai company Tour East Ltd recruit cabin crew to work exclusively for Jetstar on domestic and international flights.
The ombudsman wants Valuair and Tour East to reimburse the eight Jetstar crew at the centre of the court case with more than $7,500 they are allegedly owed in back-pay.
It is also seeking penalties against Jetstar.
"The Fair Work Ombudsman alleges Jetstar Airways was knowingly a party to underpayment contraventions," the ombudsman said.
"It alleges Jetstar rosters the foreign cabin crews on to its Australian domestic flights and is aware of the rates they are being paid."