Abstract: 【Abstract】Metabolic memory was demonstrated in some clinical trials that diabetic complications continued even though a successful control of blood glucose at later stages. This phenomenon has recently been defined as “metabolic memory”. It is still elusive how “hyperglycemic memory” influence diabetic retinopathy(DR). Among the assumed mechanisms, oxidative stress is thought to have a key role. Hyperglycemia induces dysfunction and  estruction of mitochondria in retinal cells, so reactive oxygen species are constantly released and activate downstream pathways, which lead to the metabolic memory” effect on the retina and the progression of DR. Furthermore, other mechanisms such as advanced glycation end products，epigenetic changes， as well as inflammation and apoptosis factors may also be implicated in this process.  (Int Rev Ophthalmol, 2012, 36: 375-378）