Abstract: When carbon fiber reinforced polymer (CFRP) is used to strengthen steel plate, CFRP is usually only adhered to the local part of the steel plate, which is susceptible to the influence of the peeling stress caused by the eccentricity of the specimen and the stress concentration at the lap edge. However, the peeling stress can be greatly reduced by using the full covering bonding method. The axial tensile tests of 30 CFRP reinforced steel plates with defects were carried out, and the unidirectional anti-stripping clamp was set up. The effects of adhesive type, defect length and thickness of carbon fiber plate on the reinforcement effect and failure mode were studied. The results show that the reinforcement effect of CFRP plate is significant, and the tensile strength of the specimen is signifi-cantly improved. Different adhesives have a great influence on the failure mode of the specimen. The specimen made of HJY adhesive is mainly destroyed by the adhesive, while the debonding phenomenon of the adhesive/steel appears in both Sika30 adhesive and WSB adhesive. With the increase of the defect length, the failure mode changes from the failure of CFRP plate to the failure of CFRP plate, steel plate or adhesive/steel debonding. The tensile strength of the specimen is less affected by the type of adhesive, but more affected by the size of the defect. When the defect increases, the tensile strength of the specimen decreases significantly. Based on the cohesive force model, the static mechanical tests were numerically simulated. The finite element analysis shows that the damage of adhesive starts from near the defect and then extends to both ends. However, increasing the thickness of CFRP plate can significantly increase the tensile strength of the specimen.