BackgroundNegative emotions are core predictors of adolescent mental health. While existing research has predominantly focused on the impact of risk factors such as negative life events and rumination on adolescents' emotions， the protective role of the family， particularly parental involvement， has received less attention. Consequently， the integrated mechanism connecting negative life events， rumination， parental involvement and negative emotions remains insufficiently clarified. ObjectiveTo elucidate the mechanisms linking negative life events to negative emotions in adolescents， and to verify the mediating role of rumination and the moderating role of parental involvement， so as to provide a theoretical basis for relevant prevention and intervention. MethodsA cross-sectional study was conducted in June 2025. A total of 600 adolescents from a middle school in Liangshan Yi Autonomous Prefecture， Sichuan Province， were recruited through cluster random sampling. Participants completed the Adolescent Self-rating Life Events Checklist （ASLEC）， the Rumination Response Scale （RRS）， parental involvement subscale of the Perception of Parents Scales （POPS）， and the Chinese short version of Depression Anxiety and Stress Scale （DASS-21）. Pearson correlation analysis was performed to examine the correlations among all variables. Model 4 and model 7 embedded in Process macro 4.1 were employed to separately test the mediating effect of rumination between negative life events and negative emotions of adolescents， as well as the moderating effect of parental involvement. ResultsUltimately， 534 valid questionnaires were obtained， yielding a valid response rate of 89.00%. ASLEC score and RRS score were positively correlated with DASS-21 scores （r=0.580， 0.706， P<0.01）， and ASLEC score was also positively correlated with RRS score （r=0.583， P<0.01）. Rumination acted as a partial mediator between negative life events and negative emotions， with an indirect effect of 0.531 （95% CI： 0.438–0.630）， accounting for 55.60% of the total effect. Parental involvement significantly moderated the first stage of the mediating pathway （β=-0.109， P<0.05）. ConclusionIn adolescents， rumination serves as a partial mediator in the relationship between negative life events and negative emotions， and parental involvement further moderates the predictive relationship from negative life events to rumination.