Epigenetics has an important role in gene regulation and other cellular processes. DNA methylation, as one of the main mechanisms of epigenetics, is a type of post-replication modifications. Aberrant DNA methylation can alter gene expression patterns; so, it plays a considerable role in the pathogenesis of many diseases. DNA methylated alterations in the promoter of specific genes can be used for the diagnosis and proprietary targets acting as a “biomarker”. Early diagnosis and prevention may be possible due to these biomarkers. According to recent studies, DNA methylation abnormalities have an important role in the retinogenesis and pathogenesis of retinal diseases. Retinal diseases are the main cause of blindness and severe vision loss in the world, which will continue to increase. Also, they inflict an enormous burden on society and health care systems. Therefore, it is important to focus on the better recognition and prevention of retinal diseases and finding new targets for the treatment. DNA methylation is lionized as attractive therapeutic targets due to its reversibility. Epigenetic therapy has a high potency in the treatment of retinal diseases. Here, we reviewed the DNA and histone methylation alterations in common retinal diseases, focusing on agerelated macular degeneration (AMD), diabetic retinopathy, retinal detachment (RD), retinitis pigmentosa, retinal aging, and retinoblastoma. Then we surveyed some new approaches to epigenetic therapy in retinal disorders.