Retinal vein occlusion(RVO)is the second most common cause of vision loss due to retinal vascular disease. Macular edema(ME)is a common complication of RVO and a major cause of central vision impairment. Optical coherence tomography(OCT)is a high-resolution imaging technique that can provide detailed cross-sectional images of the retina and choroid. OCT biomarkers play an important role in the early and accurate diagnosis of RVO-ME, prediction of disease progression, and assessment of visual prognosis. This article provides an overview of various OCT biomarkers for RVO-ME, including retinal thickness, disorganization of retinal inner layers, hyper-reflectivity of retinal inner layer, the integrity of external limiting membrane and ellipsoid zone, the third highest reflectance band of the fovea, hyperreflective dots, paracentral acute middle maculopathy, prominent middle limiting membrane sign, serous retinal detachment height, macular volume and choroidal thickness. These biomarkers serve as objective indicators for evaluating the severity of RVO-ME, guiding treatment decisions, and predicting visual outcomes.