Abstract: In the actual operation process, the surface of brittle carbon fiber layer of carbon fiber reinforced polymer (CFRP)-steel layered structure suffered from scratch and other damage. Therefore, it is necessary to study the damage tolerance to ensure the safe operation of the damaged composite structure. An analytical model of fracture strength at the three-point bending (3-p-b) test for CFRP-steel laminated structure with surface scratch damage was established based on the boundary effect model (BEM). And the initial scratch defects of 0.2 mm and 0.4 mm depth were prefabricated on the surface of CFRP, respectively. The feasibility of this theoretical model was verified at the 3-p-b tests. The results indicate that: (1) The fracture characteristics of CFRP-steel laminated structure at the 3-p-b tests were observed by metallographic microscope, and the structural characteristic parameter C_ch of CFRP after scratch damage was determined. The tensile strength of CFRP layer was carried out according to this analytical model, and the deviation is less than 10% compared with the tensile strength measured by CFRP direct tensile test. (2) The analytical model is a linear equation of “fracture load = tensile strength × equivalent area”. The “equivalent area” is only related to CFRP-steel laminated structure and the geometric parameters of surface crack. Therefore, the fracture strength of CFRP-steel laminated structure with surface damage can be predicted by the direct tensile strength of CFRP, and the damage tolerance design can be realized.