Concrete is one of the most applicable materials in construction. But it needs to reinforce with several reinforcement materials especially high performance fibers such as glass fibers to improve its properties. Among glass fibers, E-glass fiber has lower price but degrade in alkaline cementitious matrix. In this investigation for prohibition of E-glass fibers degradation along with better adhesion of E-glass fibers to cementitious matrix a doubled layer composite coating has been used. The first layer is a polysiloxane which it's permeability to water is too low so prevent alkali attack on E-glass fiber. The second layer is polyvinyl acetate (PVAC) having polar groups of acetate, produce calcium acetate in cementitious matrix, which stick firmly to cement. PVAC in alkaline solution can produce polyvinyl alcohol (PVA) which is again sticky to cement. This composite coating applied on E-glass fibers and used to reinforce concrete. The durability of coated fibers was investigated by alkaline stability test and SEM images. Meanwhile for studying adhesion of fibers to concrete pull out characteristics of coated fibers been investigated and compared with bare E-glass reinforced concrete.