Secondary formation of retinal proliferative fibrous tissue in refractory vitreoretinal diseases such as age-related macular degeneration proliferative vitreoretinopathy, and diabetic retinopathy sometimes causes visual loss. It is important, therefore, to control the formation of proliferative fibrous tissue in retina or contraction. Retinal pigment epithelial cells play a central role in this proliferative fibrous tissue formation mediated by epithelial-mesenchymal transition（EMT）and remodeling of the extracellular matrix. Sexual difference has been reported to have effects on the development of some vitreoretinal diseases. Sex hormones are also involved in maintaining homeostasis of retina. We have examined the action of sex hormones to contraction by RPE cells and extracellular matrix remodeling. As a result, the female hormones suppressed cell contraction of RPE cells, MMPs expression and EMT. Female sex hormones might thus prove effective for the treatment of the development and contraction of fibrous tissue in refractory vitreoretinal diseases.