QuestionFor parents of children and young people (CYP) with diagnosed mental health difficulties, what are the levels of parents’ well-being and psychological need?Study selection and analysisMedline, PsycINFO, EMBASE, AMED, CINAHL, Web of Science and Cochrane Library of Registered Trials were searched from inception to June 2023. Inclusion criteria: parents of CYP aged 5–18 years with formal mental health diagnosis. Data were extracted from validated measures of well-being or psychological needs with established cut-off points or from a controlled study.Findings32 of the 73 310 records screened were included. Pooled means showed clinical range scores for one measure of depression, and all included measures of anxiety, parenting stress and general stress. Meta-analyses showed greater depression (g=0.24, 95% CI 0.11 to 0.38) and parenting stress (g=0.34, 95% CI 0.20 to 0.49) in parents of CYP with mental health difficulties versus those without. Mothers reported greater depression (g=0.42, 95% CI 0.18 to 0.66) and anxiety (g=0.73, 95% CI 0.27 to 1.18) than fathers. Narrative synthesis found no clear patterns in relation to CYP condition. Rates of parents with clinically relevant levels of distress varied. Typically, anxiety, parenting stress and general stress scored above clinical threshold. Quality appraisal revealed few studies with a clearly defined control group, or attempts to control for important variables such as parent gender.ConclusionsThe somewhat mixed results suggest clinical anxiety, parenting and general stress may be common, with sometimes high depression. Assessment and support for parents of CYP with mental health problems is required. Further controlled studies, with consideration of pre-existing parental mental health difficulties are required.PROSPERO registration numberCRD42022344453.