The goal of the current study was to improve our understanding of why adolescence is a critical period for the consideration of declining mental health. We did this by focusing on the impact of homophobic name calling on early adolescent mental health after the transition to middle school. Because we know that homophobic name calling emerges within a dynamic peer group structure, we used longitudinal social network analysis to assess the relation between homophobic name calling, depressive symptoms, and self-esteem while simultaneously limiting bias from alternative peer socialization mechanisms. A sample of adolescents who recently transitioned to a large public middle school (N = 299; 53 % girls; M (age) = 11.13 years, SD = 0.48) were assessed. Longitudinal assessments of peer relationship networks, depressive symptoms, and self-esteem were collected during the fall and spring of the academic year. The results suggest that, after accounting for the simultaneous effect of alternative peer socialization processes, adolescent experiences of homophobic name calling in the fall predict higher levels of depressive symptoms and lower levels of self-esteem over the course of the academic year. These findings provide evidence of a significant influence of homophobic name calling on adolescent mental health.