More than 70 children and young people were abused while in Child Youth and Family care last year and no central records are being kept on the abuse.
Social Development Minister Paula Bennett revealed the information in Parliament today in response to a question from the Greens' Holly Walker.
Ms Bennett said that of the 71 cases of abuse - 30 were by CYF-approved caregivers and the rest by "third party'' caregivers.
"Thirteen have been prosecuted by police, the others have not. Even though they were substantial forms of abuse - they weren't at a level police were able to prosecute,'' Ms Bennett said.
"I am assured by the department that all of those children are now being cared for and are safe and all carers who were known to be abusing children are no longer in a position of care.''