PURPOSE: To evaluate the efficacy and safety of Bevatas, an Indian bevacizumab biosimilar, in the management of both Central Retinal Vein Occlusion (CRVO) and Branch Retinal Vein Occlusion (BRVO) (BIOS-RVO). PATIENTS AND METHODS: The BIOS-RVO study was a retrospective interventional study conducted at a single tertiary eye care facility in India. 154 treatment-naïve eyes with RVO (CRVO: 62 eyes; BRVO: 92 eyes) received intravitreal bevacizumab biosimilar (IVBb) therapy. Data on best-corrected visual acuity (BCVA), central macular thickness (CMT), and intraocular pressure (IOP) were collected at baseline and at 3, 6, and 12 months post-therapy. RESULTS: The average age of participants was approximately 55.99 (+12.56) years, with a nearly equal gender distribution (M:F = 49.4:50.6). Age differences between BRVO and CRVO groups were not significant (=0.501), but gender distribution varied significantly (=0.035), with more males in the CRVO group. Significant improvements in BCVA were observed in both CRVO and BRVO groups at 3 months, 6 months, and 1 year compared to baseline (<0.001). Both groups showed significant reductions in CMT throughout the follow-up period (<0.001). The mean number of injections was higher in the CRVO group (5.27[±1.45]) compared to the BRVO group (4.27 [±1.28]) (<0.001). Significant IOP increases were observed at 1 month (<0.001) and 6 months (<0.001) in both BRVO and CRVO groups, although not clinically significant. Safety analysis revealed no additional ocular or systemic adverse events during the study period. CONCLUSION: The BIOS-RVO study demonstrates that Bevatas is an effective and safe treatment option for both CRVO and BRVO. These findings support the use of Bevatas as a cost-effective alternative to branded anti-VEGF agents, particularly in resource-limited settings.