Objective: Determine whether a history of family social disadvantage and/or child abuse and neglect explain the overrepresentation of Indigenous Australian young people in youth detention. Methods: Maternal survey data from the Mater University Study of Pregnancy was linked with child abuse and neglect and youth justice data from the Queensland Department of Families, Youth and Community Care. Results: Indigenous Australian children were 1.81 times more likely to be notified to child protection authorities for maltreatment and 1.77 times more likely to have that maltreatment substantiated. Indigenous Australian young people were 3.07 times more likely to have a youth justice history. When adjusted for social disadvantage, the odds of the Indigenous Australian youth having had involvement with the youth justice authorities remained 2.51 times that of their non-Indigenous peers. When adjusted for substantiated maltreatment, the odds of the Indigenous Australian youth having had involvement with the youth justice authorities remained 2.83 times that of their non-Indigenous peers. When adjusted for both social disadvantage and substantiated maltreatment, the odds of the Indigenous Australian youth having had involvement with the youth justice authorities remained 2.48 times that of their non-Indigenous peers. Conclusions: The overrepresentation of Australian Aboriginal and Torres Strait Islander young people in the youth justice system, including Youth Detention, is only partly explained by their greater social disadvantage and by their greater experience of substantiated maltreatment, either separately or combined. (Contains 4 tables.)