Abstract：Modified polyvinyl alcohol (PVA) fibers with reaction activity were synthesized via suspension grafting copolymerization using glycidyl methacrylate (GMA) as functional monomer. The effects of modified PVA fiber mass fraction and drying temperature on folding endurance, tensile strength and wet strength were investigated. The results show that the desired condition for a better strength of paper is as follow: the mass fraction of modified PVA fiber is 9%, drying temperature is 110℃. At this time, folding endurance is 73 times, dry tensile strength is 70.4N, wet tensile strength is 16.2N. The structure of modified PVA fibers was characterized by TGA, which showed that the grafting copolymerization of GMA took place on the surface of PVA fiber. AFM photographs show that the formation of mastoid structure on the surface of modified PVA fiber contributes to the creation of hydrophobic surface. SEM photographs show that the length of fibers on the fractured edge of paper containing modified PVA fibers is shorter and the dissolution degree of modified PVA fibers is decreased significantly.