Abstract: Thoughening methods for epoxy resin are summarized in this paper with emphasis on the mechanism and modification methods including by rubbers,thermoplastics,inorganic nano-particles,interpenetrating polymer network(IPN),thermotropic liquid crystal polymer(TLCP) and core shell polymer(CSP).Besides,the existing problems in epoxy resin toughening are generalized and the development trend in toughening mocification of epoxy resin is predicted.