The prevalence of adolescent depressive symptoms has been rising, and maternal depression is a key predictor. This review synthesizes evidence on mechanisms of influence and on intervention research. The intergenerational transmission of risk from maternal depression appears more pronounced than that associated with paternal depression. At the biological level, genetic susceptibility and neurodevelopmental alterations underpin intergenerational transmission; at the social level, negative parenting practices and stressful family environments create a vicious cycle; at the psychological level, deficits in emotion regulation and insecure attachment amplify vulnerability to depression. Family-based interventions, including cognitive-behavioral therapy and family systems therapy, can mitigate intergenerational transmission. However, more longitudinal research is needed, and future work may integrate digital technologies to develop structured intervention protocols.