A growing number of teenage girls are risking serious injury by getting involved in public brawls, Queensland Police say.

There is evidence the fights are happening across the country and are being both planned and broadcast on social media.

Queensland Police Senior Constable Adrienne Harries, based at a school on Brisbane's bayside, said it was a growing problem.

"I've been doing this for three or four years now and seen the increase of girls fighting ... girls probably 13 to 15 years old," she said.

Senior Constable Harries said police were speaking to thousands of girls every year, trying to communicate the risks.

But she said the plans for the fights were hidden from police and parents, making it harder to stop the violence.

"Because it's a lot on social media, parents and teachers and police are missing a lot of the new stuff that's coming up," she said.

"We can't access a lot of things that they're accessing. New apps start every day and we can't keep up with all the stuff that's going on."

Ashleigh Larkin from the Queensland University of Technology's law school has investigated the issue.

She said girls were avoiding school grounds, where they could be easily identified, and instead choosing public places like local parks or shopping centres where onlookers could gather to watch them brawl anonymously.

"There's definite potential for serious injury in that they sort of have the expectation that they need to fight in a very brutal sort of manner," she said.

Ms Larkin said she was speaking to girls who fight in a bid to find ways to intervene.

"The young women I've spoken to are in the 14 to 17 age group," she said.

"They tend to fight generally because they're having a personal issue with the other young women who are involved, whether they just don't like them or they've had a fight over a boy."

She has encouraged others to share their story and help break up the brawls.