Addressing inequitable mental health harm means addressing the wider social ecosystems disproportionately affecting Māori youth, according to an analysis of Māori participants (n = 1528) from the Youth19 survey. Female sex, functional disability and sexual abuse were identified as individual risk factors for mental health harm. Housing precarity, household deprivation, bullying, and racial discrimination were identified as wider social risk factors. The concept of whanaungatanga (relationships/connection) with whānau, and feelings of safety in social ecosystems including home, school, and neighbourhoods, were key protective factors. Risk and protective factors were broadly similar across outcomes for wellbeing, depressive symptoms, suicide thoughts and suicide attempts.