The existing problems in toughened resin evaluation technology, particularly the disadvantage of the toughened resin identification method by CAI, is pointed out based on the point of view of composite structure design. It is proposed to evaluate the toughness of composites by both damage resistance and damage tolerance. Seven different toughness composites are investigated by impact and quasi-static indentation tests. Based on experimental data analysis, the parameter that is most sensitive to the damage resistance is determined as the damage parameter. The parameter to evaluate the damage resistance and its measuring method are proposed.