Abstract: The mechanical behaviours of glass fibre composite(GRP),Kevlar-49 fibre composite(KRP) and their hybrid-sandwich beams under bend/impact load have been studied.The modulus,stren gth characters and fracture features of above structures have been analyzed.It has been showed by the test results that the hybrids can improve the anti-bend properties of KRP while the impact proper ties keep the same. The dynamical bend strength(σ_a) has been introduced for evaluating the strength properties of composites under impact loading, The properties of GRP,KRP and hybrids in three-point bend have been compared with the test results of charpy impact which is similar to the former in loading way.