Victorians have been warned about a "shameless scam" involving people posing as Buddhist monks and approaching people asking for money in the name of charity.

The state's Minister for Consumer Affairs Jane Garrett said there had been dozens of complaints about the impostors over the past 18 months.

"People are posing, pretending to be Buddhist monks, complete with shaved heads and orange and yellow dress...and approaching people with begging bowls and asking for money," she said.

"They often give trinkets, perhaps some prayer beads or a spiritual guidance book, but these people are scammers and charlatans.

"They are not Buddhist monks, they are ripping off hard working Victorians and generous tourists for their own financial gain."

Ms Garrett said they were targeting people in Melbourne's CBD, particularly popular tourist areas such as Southbank, and had spread to the suburbs of Preston and Sunshine.

She said the scammers were not part of a registered charity or the Buddhist faith.

"This is causing issues, not only for people who think they are giving money for a good purpose, but its also undermining the genuine charitable works the Buddhist faith does," she said.

"If they've asked you for money, they're not a monk.

"Genuine monks do have a practice of having gifts or giving alms as part of their religion but it is meant to be a generous donation of those who wish to give without any solicitation whatsoever."

Ms Garrett said they often request as little as a few dollars to as much as $20.

She warned some had been aggressive towards the public and had recently become more brazen in their approach.

"We think it's becoming increasingly organised, whether it's backed by some broader organised gang racket we're not sure, but it's certainly its a group of people and a growing group people," she said.

"What I'm particularly concerned about is that at times of disaster, conmen and women become more frenzied in activity.

"People feel more vulnerable ... and in generosity of spirit people want to help out others."

If people were approached by someone asking for a donation, Ms Garrett said they should request to see some identification, ask what the work of the charity was and where the money was going.

Victorians, South Australians warned about fake bushfire charities

It came as the Australian Competition and Consumer Commission also warned against scammers who were taking advantage of people's generosity after the the recent bushfires in South Australian and Victoria.

It said con artists in South Australia had been pretending to be from the Country Fire Service and asking for donations door-to-door.

ACCC spokesman Michael Schaper said people should do research into a charity before donating money and deal directly with the organisation.

"You can be approached online through social media, you might receive an email, you might get a phone call, you might even get a knock on the door," he said.

"[You're] better off to actually go to the organisation in question, first of all to verify that the details that you might have got are legitimate, but also secondly to see how they want you to contribute.

"Some organisations have preferences about where they want the money sent and why.

"If you've got a real commitment to making sure that the money goes to the right place, that's probably going to help them as well as yourself."