Scammers, often pretending to be from government departments, have intimidated people into handing over nearly $9 million this year.
The Australian Competition and Consumer Commission says the rort relies on fear, intimidation and people's instinct to comply with authority.
So far this year Scamwatch has received more than 18,000 reports of these scams, an increase of 40 per cent compared to all of 2019.
The scams are mainly phone-based and impersonate various officials, such as police, ATO officers or government investigators.
People 24 and under reported losing more than $4.1 million to threat-based scams and women reported losses three times higher than men.
"It is extremely concerning that young people are being so severely emotionally and financially impacted by threat based scams," ACCC Deputy Chair Delia Rickard said in a statement on Monday.
Three-quarters of the losses - $6.5 million - targeted Mandarin-speakers in Australia with the caller impersonating authorities such as the Chinese embassy, police or other government officials.
"Threat based scams disproportionately impact people with English as a second language, including foreign students, who may not fully understand Australian law," Ms Rickard said.
© AAP 2020