The diabetic retinopathy is a disease of the retina that caused by diabetic mellitus. People with diabetes can have a eye disease called diabetic retinopathy. This occurs when the high blood sugar causes damage to the blood vessels in the retina. These blood vessels can swell and leak and then can close and stopping blood from passing through. Sometimes abnormal new blood vessels grow on the retina. All these causes blindness among diabetic patients It’s caused by damage to the blood vessels of the light-sensitive tissue at the back of the eye called retina. At first, diabetic retinopathy may cause no symptoms or only mild vision problems. The causes of the diabetic retinopathy is, over time too much sugar in the blood that can lead to the blockage of the tiny blood vessels that nourish the retina, cutting off its blood supply. As result the eye attempts to grow new blood vessels which is abnormal and that can leak easily. Diabetic retinopathy poses a considerable worldwide public health and economic burden due to the growing number of people with diabetes. Since diabetic retinopathy may result in visual impairment or blindness, it can also have a profound impact on patients’ lives. Early detection of retinal abnormalities is essential in preventing diabetic retinopathy and loss of vision. Laser photocoagulation only targets advanced stages of disease and does not usually restore vision. Systematic screening for diabetic retinopathy can substantially reduce the risk for visual impairment and blindness, and the key to achieving national targets.