Diabetic retinal disease(DRD)is a disease with a sharp increase in the proportion of retinal disease(RD). Diabetic macular edema is the leading cause of vision loss. The treatment of diabetic macular edema has always been a hot topic in medicine. The diagnosis and treatment of diabetic macular edema is the latest treatment guideline for diabetic macular edema published by the European Association of Retinal Experts. It is considered to be the most representative guide at present. Detailed interpretation in this article will help the majority of ophthalmologists have a new understanding of the diagnosis and treatment of diabetic macular edema.