Stressors have been identified as significant vulnerability factors in the development of adolescents' depression. The present study focused on the relationship between depressive symptoms and two types of interpersonal stressors in the schoolyard, namely teacher-student interaction stressors (TSIS) and peer interaction stressors (PIS). More importantly, rumination and co-rumination were examined as two possible mechanisms to account for these relationships. A convenience sample of 570 Chinese adolescents aged from 12- to 19-years-old participated in this research. Results indicated that TSIS and PIS were significantly related to participants' depressive symptoms. Furthermore, rumination partially mediated the relationship between PIS and depressive symptoms. Co-rumination was a partial mediator between both types of interpersonal stressors and depressive symptoms. Hence, rumination and co-rumination might serve as two mechanisms linking interpersonal stressors in the schoolyard and depressive mood in adolescence. The findings are discussed in the light of related literature and potential implications for school practitioners.