Overseas students getting as little as $6 an hour to work in local Asian restaurants are too afraid to complain for fear of losing even the meagre wages paid by their unscrupulous bosses.

Flinders University's international officer Zheng Shan says as many as four out of five of the campus's Chinese students work part-time in Asian eateries, where many are paid about half the award wage of $15 for adults aged above 20.

He says the language barrier and limited job vacancies in Adelaide means students have little option other than to take the work, which is usually cash in hand.

"Six dollars to $8 per hour is a very common pay in Asian restaurants," he said.

"They are paid on the table cash and they know it's not right but in Adelaide it is very difficult to find part-time jobs so they normally wouldn't tell anybody about their situation."

Mr Shan worked in a Vietnamese restaurant for a month and was paid $6 per hour for the first week.

"They called it ��training' and then after that I was paid $8," he said.

Mr Shan said a September 2009 survey of Flinders' Chinese students found most of the 27 respondents working part-time were paid less than $10 per hour.

"Many of my friends are also working for only $6 to $8 per hour," he said.

Mr Shan called for international students to be better educated about their working rights before coming to Australia. "We have to make people be aware because if most people choose to be silent about speaking out to protect their rights, it will stay the same," he said.

Employee Ombudsman Stephen Brennan was "very aware" of the issue but said most overseas students did not report underpayment because they were unaware of their rights and needed the work.

"Overseas students are vulnerable because their introduction to Australia is more about study and employment opportunities at the end of it," he said.

"Ninety-nine out of a hundred will be paid cash and appreciate the extra money, but it's that one in a hundred who will either fall over, cut or burn themselves and they don't have WorkCover or superannuation or any cover at all."

Mr Brennan said he hoped to launch an information campaign early next year, involving flyers and stickers at Adelaide universities and speaking with students about their rights.

"We'll team up with SafeWork SA and the Federal inspectors and consider the issues that are bubbling away and collectively, start a campaign," he said.But the timeframe was dependent on workload and resources, Mr Brennan said.

Restaurant and Catering SA chief executive Sally Neville said the association "would never endorse paying someone below the minimum wage of $15".

"If someone is accepting that rate of pay, they should review that position and demand their rightful wage," she said.

Mrs Neville disagreed there were limited jobs for international students.

"Every week in the hospitality section of the job guide there are hundreds of casual jobs available," she said.

"I dont think they would be so destitute that they would have to accept an underpaying job because of lack of employment options."