Ceramide is known as the one of the most important ingredients in the phospholipids that organize the horny layers, protecting the skin. It is discovered that the lack of the ceramide evaporates the skin and makes it very dry, also causes the various skin troubles worse. It is known that as Ceramide applied in the skin and penetrated to lipid layers of the horny layers, the topical applying ceramide prevent the skin dry, improves skin troubles and keeps the skin heathy long time. Especially, the quantity of ceramide is directly relevant to the skin barrier function which prevent horny layers evaporating. It will be clear that Applying ceramide to skin not only makes the skin barrier be formed and maintained, but also recover the damaged skin barrier. Then we make an experiment that when we apply emulsified ceramide products to damaged skin, how the damaged skin recover well and the skin barrier be formed effectively. It was a result that the skin which applied with ceramide was much more moist than the control. Also there is a significant difference between the two groups in TWEL, so it is sure that ceramide has a effective function as a skin barrier.