We report a case of central artery obstruction in a 55-year old man who had non proliferative diabetic retinopathy. Three years later, examination found no diabetic retinopathy in the eye that had central artery obstruction, and more advanced non proliferative diabetic retinopathy in the fellow eye. Pathogenic mechanisms for diabetic retinopathy regression after central artery occlusion could be the optic atrophy and ischemia of the inner retina associated to the decrease in retinal blood flow.