Abstract: Light weight and flexibility of the large aircraft make aerodynamic and structural coupling strengthen, as a result, the coupling effect must be considered while designing the aircraft structure. CFD/CSD coupling method cannot meet the requirement of the engineering. The surrogate model method has been used in the aerodynamic shape design for its high efficiency. In the paper, an aerodynamic optimization method based on the Kriging surrogate model was established to optimize the structure stiffness. The method used the maximum expected improvement (EI) function for adding the sample points to improve the accuracy of the surrogate model, and adopted the revised particles swarm optimization algorithm. The results show that the optimization method based on Kriging surrogate model can deal with the complicated problem with global optimization, and the flight drag coefficient is reduced at cruise state while remaining the lift coefficient and longitudinal stability not worsen.