We investigated the effects of perceived parenting styles, causal attributions for academic success/failure, and perceived school performance (PSP) on adolescents' psychological well-being (PWB). Participants were 200 Brazilian adolescents who answered the Parenting Styles & Dimensions Questionnaire, the Psychological Well-Being Scale, and the Rating Scale of Causal Attributions for Academic Success/Failure (RSCA). The results showed that adolescents' PWB was predicted by authoritative parenting style (APS), internal and controllable attributions (appropriate motivations to cope with academic success/failure; ICASF), and PSP. In addition, we tested a mediation model showing that the ICASF mediated the relationship between APS and PSP, which in turn led to better PWB. These results highlighted the relevance of parenting styles and school-based causal attributions for the understanding of adolescents' mental health. Our findings can support interventions that enable more effective teaching-learning processes, which are associated with higher levels of mental health for the adolescent population.