Abstract: Diabetic retinopathy is an eye-disease that is very common among people who are suffering from diabetes. Glaucoma is also an eye disease that damages the optic nerve head and leads to vision loss. Optic disc localization is important for the early detection of Glaucoma and clinical features of diabetic retinopathy such as microaneurysms, hard exudates, soft exudates, hemorrhages, neovascularization and macular edema. This study examines the optic disc localization methodologies in two dimensional retinal images acquired from a fundus camera. The aim of this study is to review and categorize the optic disc localization techniques and methodologies. Researchers intend to give the reader a frame work for the existing research and discuss the current trends and future direction. The performance of various methods is compared and analyzed on publicly available DIARETDB0, DIARETDB1, DRIVE, STARE and MESSIDOR databases.