In order to ensure the subsequent stability of the composite repaired structure, it is required to use nonlinear ultrasonic Lamb wave to detect the health of the repaired area. Experimental and simulation studies of tensile damage in composite plate before and after adhesively-bonded repaired composite plates were conducted using nonlinear ultrasonic Lamb wave higher harmonic response technique. Finite element modeling was performed by ABAQUS software, the Hashin criterion was used to predict the tensile damage evolution of the matrix, and a smoothing analysis step was introduced in the tensile process. Finally, the propagation process of Lamb wave was simulated by applying displacement loads. On the basis of experimental verification of the feasibility of the simulation model, the relationship between higher harmonic response of nonlinear Lamb wave and tensile displacement, as well as the influence of different tensile damage degrees on the nonlinear parameters were investigated. The results show that compared with the unrepaired structure, the damage area, the second and third nonlinearity parameters in the adhesively-bonded repaired structure after stretching are significantly reduced. It indicates that this method can evaluate the effectiveness of engineering adhesively-bonded repair. With the increase of the tensile displacement, the second and third harmonic amplitudes and nonlinearity parameters first increase and then decrease, and reach the maximum at the tensile displacement of 1mm. The nonlinear Lamb wave high order harmonic technology can effectively predict the tensile damage of composite before and after repair.