Diabetic retinopathy(DR) is the leading cause of new onset blindness among working-aged groups in industrialized countries, and its incidence is expected to increase along with the rising incidence of diabetes mellitus. Primary interventions such as strict glycemic control, tight blood pressure regulation, and lipid-lowering therapy can significantly reduce the risk of DR occurrence and progression. Currently, laser photocoagulation is the mainstay of treatment of proliferative DR and some cases of diabetic macular edema (DME). However, a considerable number of DR patients still suffer from severe visual impairment in spite of the application of laser photocoagulation and even of pars plana vitrectomy. Considering the limitations of current DR treatments, ongoing efforts have been devoted to the development of new therapeutic strategies, and it has become necessary to focus on pharmacologic treatment. Since inflammation has been identified as playing a substantial role in the pathogenesis of DR, corticosteroids with an anti-inflammatory effect can be included in the treatment of DR, though this may cause cataract and intraocular pressure elevation. The recent discovery of inhibitors of vascular endothelial growth factor is a revolutionary event in the management of DR, specifically DME. Some new agents aiming at the process of angiogenesis and increased vascular permeability are still under investigation, offering hope for a more effective future treatment of this sight-threatening disease. This paper reviews the current state of knowledge of the clinical presentation, preventive management, and clinical therapeutic strategies of DR and DME.