Problem-solving (PS) training is a common ingredient of evidence-based therapies for youth depression that can be delivered as part of broader therapy packages or alone. As a stand-alone treatment, Problem-Solving Therapy (PST) is effective for adult depression. Aims: This scoping review aimed to provide an overview of the evidence concerning PS training for depression in youth aged 14 to 24. We searched five bibliographic databases and the grey literature. We included four randomized control trials (524 participants) comparing PST with waitlist controls or comparator interventions; four secondary analyses of PS-related concepts as predictors, moderators, or mediators of treatment response; 23 clinical practice guidelines (CPGs); and insights from a youth advisory panel. One high-quality study found PST helped with personal problems but was not significantly more effective than the control at reducing emotional symptoms. Exploratory evidence suggests PS training may enhance treatment effectiveness if provided alongside other skills in cognitive behavioural therapy. CPGs do not recommend PST as a first-line treatment for youth depression. Exploratory meta-analysis showed a small effect (Hedges’ g = -0.34; 95% CI: -0.92 to 0.23) with high heterogeneity and a very low quality of the evidence. After removing one study at high risk of bias, effect size and heterogeneity were strongly reduced (g = -0.08; 95% CI: -0.26 to 0.10). High-quality trials of PST alone or with other therapies are needed. As per suggestions by youth advisors, PS training may need to be reworked to ensure it is youth-driven, strengths-based, comprehensive, and personalized.