Neither Queensland's department of child safety nor a private agency did enough to protect a girl bashed to death by her mother, a coroner has ruled.

The eight-year-old was found dead at her Cairns home after being repeatedly struck with a vacuum cleaner pole in November 2011.

The girl's death is being examined by the Queensland Coroner. Credit:Louie Douvis

The mother is serving seven years' jail after last year pleading guilty to manslaughter.

An inquest examining the involvement of government departments, private agencies and the girl's extended family was held this month in Cairns.