Background and Objective: To compare efficacy of monthly treatment with bevacizumab or ranibizumab for macular edema due to retinal vein occlusion. Patients and Methods: Randomized, multicenter, comparative trial (ClinicalTrials.gov identifier: NCT01428388). Participants were randomized 1:1 to receive monthly treatment with bevacizumab or ranibizumab. The primary outcome was change in central foveal thickness at 6 months compared to baseline. Results: The trial randomized 98 patients to treatment with bevacizumab or ranibizumab. At 6 months, there were no differences in change in central foveal thickness between groups (bevacizumab: mean reduction of 212.6 μm, 95% confidence interval [CI], -288.3 to -137.0; ranibizumab: mean reduction of 243.8 μm, 95% CI, -309.6 to -178.0; P = .72, analysis of variance [ANOVA]). Both groups showed similar functional outcomes (bevacizumab: 0.33 logMAR gain, 95% CI, -0.47 to -0.18; ranibizumab: 0.34 log- MAR gain, 95% CI, -0.45 to -0.23; P = .38, ANOVA). Conclusion: In the treatment of retinal vein occlusion, bevacizumab and ranibizumab have similar effects on reducing macular thickness and improving visual acuity.