The increasing global prevalence of diabetes is a critical problem for public health. In particular, diabetic retinopathy, a prevalent ocular complication of diabetes mellitus, causes severe vision loss in working population. A better understanding of the pathogenesis and the development of new pharmacologic treatments are needed. This paper describes the relevance between Rho/ROCK pathway and the pathogenesis of diabetic retinopathy from its early to late stages. Moreover, the therapeutic potential of ROCK inhibitor in the total management of diabetic retinopathy is discussed.