The current investigation uses longitudinal data to begin to understand the correlates of gender integration and youth emotional adjustment. Participants were 207 adolescents (mean age = 11.11 years, 53% female). The results demonstrated that, when compared to only having gender-segregated peer affiliates, gender-integrated peer affiliates, as well as the transition from gender-segregated to gender-integrated peer affiliations from the beginning to the end of the sixth-grade academic year was associated with significantly higher levels of self-esteem. Descriptive data also indicate that gender segregation was associated with lower levels of depressive symptoms, although the effects on depressive symptomology did not reach traditional levels of statistical significance. The findings highlight the important emotional impact of gender-diverse peer relationships among young adolescents.