H₂S is the third kind of endogenous gaseous signal molecule after NO and CO. Numerous studies have shown that H₂S was involved in vasodilation, inhibiting smooth muscle proliferation, protecting hypoxic neurons, anti-inflammatory, anti-oxidation stress, anti-ischemia/reperfusion injury and other physiological/pathological processes. The present studies mainly concentrate on the circulatory system and nervous system rather than diabetes mellitus and diabetic retinopathy(DR). But the physiological and pathological effects of H₂S and the pathological process of DR have various correlations in many ways in theory. In this paper, the progress and protection of H₂S on the pathogenesis of DR are reviewed at the angle of molecular and cellular.