Objective: Gay and bisexual men have significantly higher rates of depression than heterosexual men. The minority stress theory (Meyer, 2003) proposed that distal minority stressors, like interpersonal discrimination, contribute to this disparity. The psychological mediation framework (Hatzenbuehler, 2009) posited several psychosocial mechanisms through which distal minority stress creates elevations in depression among sexual minorities. Despite accumulating support for this framework, there are a number of limitations to existing research, including largely relying on cross-sectional designs; focusing on a small subset of mechanisms and moderators; and using nonprobability samples. Method: We recruited a sample of gay and bisexual men (N = 502) obtained from a population-based data set of U.S. adults. Participants completed validated measures of distal minority stress (i.e., interpersonal discrimination), psychosocial mechanisms (i.e., rumination, emotional clarity, and social support), identity-related moderators (i.e., identity centrality, stigma consciousness, and sexual orientation identity), and depressive symptoms at baseline, 6-month follow-up, and 1-year follow-up. Results: Rumination (b = 0.38, 95% CI [0.13, 0.84]), lack of emotional clarity (b = 0.43, 95% CI [0.11, 0.83]), and lack of social support (b = 0.21, 95% CI [0.04, 0.45]) each individually mediated the prospective relationship between interpersonal discrimination and depressive symptoms, controlling for initial symptoms, age, and education. These indirect effects were not moderated by identity-related characteristics or sexual identity. Conclusion: Our study provides some of the strongest empirical evidence for the psychological mediation framework to date and suggests targets for interventions focused on reducing the mental health consequences of minority stress for sexual minority men.