This study examined the associations between parental involvement in adolescents' organized after-school activities and adolescents' motivational beliefs. Data were reported by 231 Mexican-origin and European American adolescents who participated in an organized after-school activity (57% female, M[subscript age] = 12.37, SD = 0.54) and their parents. Overall parental involvement positively predicted adolescents' motivational beliefs (i.e., ability self-concepts and values). Latent profile analyses revealed unique patterns across the three types of parental involvement (i.e., instrumental support, verbal encouragement, and activity connections) that differentially predicted adolescents' motivational beliefs. This approach highlighted the importance of parent-activity connections. Adolescents of parents who reported average instrumental support and verbal encouragement, but low activity connections had lower motivational beliefs compared to adolescents whose parents had average involvement across all dimensions. There were no differences by adolescent ethnicity. The current findings underscore the importance of parental involvement in promoting positive youth development.