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. This scoping review provides 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; 24 clinical practice guidelines (CPGs); and insights from a youth advisory panel. Quantitative evidence was mixed and of variable quality. One high-quality study found PST helped with personal priority problems but was not significantly more effective than the control at reducing depressive symptoms. Exploratory evidence suggests PS training may enhance treatment effectiveness if provided alongside other skills in cognitive behavioral therapy. CPGs currently do not recommend PST as a first-line treatment for youth depression. An exploratory meta-analysis of PST for depressive symptoms failed to reach significance and showed high heterogeneity; removing one study at high risk of bias reduced heterogeneity and suggested no overall effect (g = -0.06; 95% CI: -0.25 to 0.12). Well-powered trials of PST alone or with in 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.