The incidence of diabetes mellitus is increasing worldwide. Over time, diabetes is associated with the development of diabetic retinopathy, a major cause of vision loss globally. Research has demonstrated factors associated with the onset and progression of the disease. Despite advancements in understanding the importance of optimizing care, the cases of vision loss due to diabetic retinopathy are also increasing. The epidemic of this systemic disease and the retinal manifestations will be discussed in detail in this chapter.