Split Hopkinson pressure bar(SHPB) device was used to conduct the experimental study on the dynamic tensile properties of mortars mixed with ultra high molecular weight polyethylene(UHMWPE) and polyvinyl alcohol(PVA) fibers. The effects of strain rate on dynamic splitting tensile strength and dynamic increase factors of specimens were analyzed and the fitting formula of uniform splitting tensile strength based on strain rate of fibrous mortars static and dynamic load bearing was proposed；combined with the failure mode and energy dissipation, the splitting tensile strength of fibrous mortar was analyzed. Test results show that, compared with the PVA fibrous mortar, impact tensile strengthening effect of UHMWPE fibrous mortar is prominent, also different types of PVA fibrous mortar has obvious difference on dynamic mechanical properties. Furthermore, the dynamic tensile strength, dynamic increase factor and energy dissipation of fibrous mortar increasing with the accelerating of strain rate, e.g., the maximum dissipation energy Ws,max is increased about 15% with 18kg/m3 UHMWPE fibrous mortar compared with the plain specimen.