© 2020 Wolters Kluwer Medknow Publications. All rights reserved.Purpose: To compare the long-term results of the patients with branch retinal vein occlusion (BRVO) secondary to Behçet's syndrome (BS) with the patients with unknown etiology. Methods: Medical records and optical coherence tomography (OCT) imaging results of the patients with BRVO secondary to BS and with unknown etiology were reviewed retrospectively between 2016 and 2018 at a single center. The anatomical location of the BRVO, involvement of the macula, application of laser photocoagulation, and intravitreal injection were evaluated. Results: Twenty-eight eyes of 23 patients with BRVO secondary to BS as the study group and 22 eyes of 19 idiopathic BRVO patients as the control group were included in the study. The mean duration of follow-up after the development of BRVO was 74.6 ± 57.4 months in the study group and 63.6 ± 59 months in the control group. The rate of bilaterality, macular involvement, and application of laser photocoagulation was not statistically significantly different between the groups. However, the frequency of injection requirement was significantly lower in the patients with BRVO secondary to BS in comparison to the control group (P= 0.009). Conclusion: Although the treatment of BRVO is laser photocoagulation and intravitreal injection of anti-VEGF agents or dexamethasone implant, the patients with BS might respond very well to systemic immunomodulatory agents in case of BRVO. Thus, rearrangement of the immunomodulatory treatment before starting intravitreal injections should be considered in the patients with BRVO secondary to BS.