Adolescent wellbeing in Mozambique is a critical area of concern, with mental health issues affecting a significant portion of the population. A systematic review was conducted using electronic databases to identify relevant studies. Studies were selected based on predefined inclusion criteria related to the impact of school-based mental health programmes on adolescent wellbeing in Mozambique. The analysis revealed a moderate positive effect of school-based mental health interventions, with an estimated standardised mean difference (SMD) of 0.45 (95% CI: 0.32-0.58). School-based mental health programmes show promise in improving adolescent wellbeing in Mozambique, though further research is needed to refine intervention strategies. Future studies should focus on longitudinal follow-up and the implementation of culturally adapted interventions tailored to the local context. adolescents, mental health, school-based interventions, Mozambique, systematic review The empirical specification follows $Y=\beta_0+\beta^\top X+\varepsilon$, and inference is reported with uncertainty-aware statistical criteria.