A Canberra woman has been sentenced to 200 hours of community service for assaulting her seven-year-old daughter.

The ACT Magistrates Court heard the child rang triple-0 three times asking for help in December 2016.

The child later told police her mother had hit her once on the shoulder and twice on the back when she came out of her room to go to the toilet.

The court was told the woman argued with police that she was entitled to discipline her child.

"I can smack my f***ing kids if I want to," she told police.

"I can smack my kids as long as the mark doesn't last 24 hours."

A victim impact statement from the girl, who now lives with her grandparents, was read to the court.

"I am scared of her, I never want to go back," the statement read.

"I am happy now … and scared of mum and dad's [home]."

Behaviour labelled 'chastisement gone too far'

In a separate statement the child's grandmother said the girl had suffered many behavioural and learning problems, but had improved greatly since leaving her parents home.

The mother's lawyer described the case as chastisement gone too far, and said she now regrets her actions.

The court heard the 30-year-old mother had left home at a young age, and lived with a violent ex-partner before meeting the father of her children.

The court heard she had worked on improving her parenting since the incident late last year.

Woman's actions towards child 'deeply troubling'

Magistrate Bernadette Boss said the incident was serious, and warranted a response from the court.

"This was a significant assault on a child," she said.

"It was a very significant breach of trust.

"Children are the most vulnerable part of our community and everyone has a responsibility to protect children."

Magistrate Boss addressed the woman directly, telling her discipline does not include that sort of treatment.

"It's deeply troubling you thought you had a right to assault your child," she said.

"It's deeply troubling you thought you could do it so that the marks only lasted 24 hours."

The woman will also have to meet the conditions of a two-year good behaviour order.