With the wide use of FRP strengthened structures,the problem of their durability has been highlighted and concerned.The durability of saturating resin which is one of components of fiber reinforced polymer and adhesive material of FRP and concrete,affects the property of FRP reinforced structures.Wet-dry cycling is one of the factors which influences the durability of resin.The durability of two types of resin caused by wet-dry cycling was studied in this article.The change tendency of mechanical behavior of the resin was investigated and the test results were analyzed.The results showed that the change tendency of mechanical behavior of two types of resin was different under the same wet-dry cyching condition.