<p>Interparental conflict is a well-established risk factor for adolescent well-being. However, the moderating role of teacher-student relationships on the longitudinal association between interparental conflict and adolescent well-being is unclear. Using a multilevel framework, this study employed a 4-wave longitudinal design over two years to examine the interaction between teacher-student relationships and interparental conflict in adolescent subjective well-being. Participants were 484 adolescents (<i>M</i>_age=14.33 years, SD = 1.62) from a secondary school in southwest China. The result indicated that adolescents who reported higher cumulative experiences of interparental conflicts also perceived significantly less subjective well-being than their peers who reported fewer conflicts in the past two years. Moreover, the teacher-student relationship at the between-person level buffered the adverse association of interparental conflicts with subjective well-being at the within-person level among middle school students. These findings suggest that persistent exposure to interparental conflicts was associated with individual differences in subjective well-being, and consistently perceived positive teacher-student relationships buffered the negative association of interparental conflicts with subjective well-being among early adolescents, highlighting the protective effects of quality teacher-student relationships across contexts.</p>