Despite research documenting the impact of parenting styles on adolescent development, the bidirectional dynamics between adolescents’ perceived parenting styles and their prosocial behavior, particularly when simultaneously considering the role of emotion regulation, remain underexplored. This study used the random intercept cross-lagged panel model (RI-CLPM) to examine bidirectional relationships between adolescent-perceived parenting dimensions (emotional warmth, psychological control, and harsh parenting) and adolescent prosocial behavior, while exploring emotion regulation strategies as mediators. The study utilized a three-wave longitudinal design with 719 middle school students (47.43% female; Mage = 12.11 years, SD = 0.41) from southwestern China, with one-year intervals between assessments. Results showed that at the within-person level, adolescent-perceived parental warmth and adolescent prosocial behavior formed a positive bidirectional relationship mediated by cognitive reappraisal. Parental psychological control predicted decreased prosocial behavior through increased expressive suppression, while harsh parenting reduced prosocial behavior by inhibiting cognitive reappraisal strategies. Multi-group analysis revealed that the indirect pathway from parental psychological control to prosocial behavior through expressive suppression was significantly stronger for female than male adolescents. These findings identify key psychological mechanisms promoting adolescent social adaptation within family systems, highlight emotion regulation’s central role in the bidirectional relationships between parenting and adolescent development, and offer important implications for family interventions.