It is well known that hotel room cleaners are among Australia's lowest paid workers, but today a new report alleges many of them are also being ripped off by their employers.

The hospitality union and a migrant women's group documented the working conditions of hundreds of cleaners at some of Melbourne's most opulent hotels.

The report was launched by former Victorian premier Joan Kirner, who says Melbourne's reputation as an events city is being propped up by the exploitation of migrant women.

Ms Kirner launched the report, Heartbreak Hotels, pointing to the story of one worker who says she is paid $5 to clean a room that costs guests $300 a night.

"Do we want a kind of nation and state that says there are different levels of people - some who are entitled to a voice, some who aren't?" Ms Kirner said.

"Do we want a nation that says some are entitled to fair pay, some are not?"

The report was complied by the Liquor, Hospitality and Miscellaneous Union (LHMU) and the Immigrant and Refugee Women's Coalition.

It is based on interviews with 330 room attendants who work at 23 of Melbourne's four and five-star hotels.

The report says it takes at least 45 minutes to clean a hotel room, but many workers are given just 15 minutes to complete the task, and when it is not done they are pressured to stay back and finish the job.

Yaima Izquierdo has been working as a room attendant since she arrived in Australia from Cuba 18 months ago.

"So at the end of the day, we have to finish the rooms that have been given to us. Doesn't matter what time you finish, but if you finish late, we are not paid for that," she said.

"So that means no overtime."

Hotel cleaners get paid $16 an hour, but three-quarters of the workers who were surveyed said they were not always paid when they worked overtime.

Fifty-eight per cent said they felt pressured to stay until the work was done.

Many felt their jobs were at stake. Others reported their pay would be docked or their shifts changed if they did not do the overtime.

The report found three-quarters of the workforce were women and just 12 per cent were born in Australia.

Dignity

The executive officer of the Victorian Immigrant and Refugee Women's Coalition, Melba Marginson, says cleaning hotel rooms is hard work which typically involves 22 separate tasks per room and can result in injury.

"Most of the women have chronic back and shoulder injuries, also hip and hands - especially repetitive - RSI - repetitive work.

"In fact, 52 per cent of those that we studied, we researched, had all sorts of different injuries."

Ms Marginson says hotel managers are using a number of methods to get cleaners to work unpaid overtime.

"They are made to sign that [they] have to finish this certain number of rooms," she said.

"[And] we know for a fact, migrant workers always look at work as a decent job, whatever it is, and that we have dignity in doing that work.

"So, part of the commitment is, when you sign up for 19 rooms, you finish 19 rooms.

"So what happens is they couldn't finish 19 rooms. And so they had to work overtime but then the supervisors don't pay for that."

Eyes closed

Ms Kirner helped set up Melbourne's Major Events Committee with the aim of making Melbourne the events capital of Australia.

She says the city regularly stages brilliant and profitable events, while closing its eyes to the workers who help make them possible.

"As former premier of Victoria, I am calling on the committee to take an interest in this report, because if they take an interest then they are fulfilling their full charter," she said.

"They were set up by myself, Don Walker, and others, to bring the best events to Victoria.

"Well, guess what? These room attendants are part of providing the best quality and the best experience for the Victorian community, and particularly the international community."

However, already some of the report's findings are being questioned.

The LHMU says workers at three Hilton Hotels are not given enough time to clean properly and are not always paid for overtime.

A spokeswoman for Hilton Hotels Australia says it is disappointed the union did not share its survey findings with Hilton, and its report is at odds with Hilton's internal surveys.