Atwell College brawl: Parents 'disgusted' as teachers fail to intervene in schoolyard fight

A Perth father is demanding answers after teachers failed to intervene during a violent schoolyard fight.

Video of the brawl at Atwell College on Tuesday shows two teenage boys repeatedly punch each other as two teachers look on.

Students told 9NEWS the fight only ended after another member of staff got involved.

The father of one student said he couldn't believe teachers stood by as the classmates traded blows.

"My daughter showed me and I was disgusted," the parent said.

"The teacher could have just pushed them apart and said, 'right nup back to your class', they didn't.

"They just stood there and watched."

The teacher's union has defended the staff member's actions.

Teachers are not expected to intervene in physical fights because they could face the possibility of criminal assault charges from parents, or integrity action from the state's Department of Education.

That explanation did not impress the father.

"If it's the education department's rules, it should be changed," he said.

"Because now fights are going worse and bullying is getting worse and when's it going to stop?"

The WA education department acknowledged the vision was disturbing and said it will investigate.