Diabetic keratopathy is one of the common complications of diabetes in the eye, the main clinical manifestations include dry eye diseases, punctate keratitis, slow regeneration of cornea epithelial, recurrent epiththelial erosions, degeneration of corneal sensitivity and corneal edema. The main pathogenesis is AGES, polyol pathway, the changes of proteinases, etc. This article mainly reviews the pathogenesis of its main clinical manifestations,expect to provide new ideas for clinical treatment.