Adolescent self-harm is an emerging public health challenge. It is associated with later psychiatric and substance use disorders, unemployment and suicide. Family interventions have been effective in a range of adolescent mental health problems and for that reason were reviewed for their effectiveness in the management of adolescent self-harm. The search identified 10 randomised and 2 non-randomised controlled trial conducted in the high-income countries. For the most part the evidence is of low quality. The interventions were classified as brief single session, intermediate-level and intensive family interventions depending on the intensity and duration of treatment. Brief interventions did not reduce adolescent self-harm. Intermediate interventions such as the Resourceful Adolescent Parent Programme, Safe Alternatives for Teens and Youth Programme and attachment-based family treatment were effective in reducing suicidal behaviour (effect size 0.72), suicide attempts (P=0.01) and suicidal ideations (effect size 0.95), respectively in the short-term with an absence of long-term follow-up data. Intensive adolescent interventions such as dialectical behaviour therapy and mentalisation-based therapy reduced suicidal ideation (effect size 0.89) and self-harm (56% vs 83%, P=0.01), respectively. The persistence of effects beyond the intervention end point is not known in many interventions. Early involvement of the family, an evaluation of the risks at the end of an acute crisis episode and a stepped-care model taking into account level of suicide risk and resources available to an adolescent and her/his family are likely to promote better outcomes in adolescents who self-harm.