As one of the serious complications of diabetes, diabetic retinopathy(DR)has become a main eye disease which causes blindness. The occurrence and development of DR is related to many factors. The pathogenesis is complicated, and the mechanism has not been clear. Early data suggest that the occurrence and development of DR has relations with many factors such as blood sugar level, diabetes duration and the environment. Among the factors, mitochondrial dysfunction and oxidative stress is the important mechanisms of DR and has become research focus in recent years. Consequences of mitochondrial dysfunction within cells include elevation of the rate of reactive oxygen species(ROS)production due to damage of electron transport chain proteins, mitochondrial DNA(mtDNA)damage, and loss of metabolic capacity. Clear understanding on the mechanism of mitochondrial functional change under high sugar level and oxidative stress response in the occurrence and development of DR is of great significance on prevention and cure of DR. In this article, the development of mitochondrial metabolism and oxidative stress of DR is reviewed.