Abstract: In order to ensure that the aerodynamic performance of high aspect ratio wing in cruise flight can meet the design targets, it is necessary to carry out the jig shape design in the wing design stage. The wing stiffness has a significant effect on the aerodynamic loads, which is one of the important factors affecting the aeroelastic characteristics. Robustness analysis of jig shape design with various stiffness properties was conducted based on CFD/CSD method. The aerodynamic characteristics evaluation model was established with the stiffness value as the independent variable. The sensitivity analysis of the stiffness was carried out with the wing twist angle and lift efficiency as constraints. The research results, providing support for the static aeroelastic evaluation of wing stiffness in the engineering design, show that the vertical bending stiffness and twist stiffness are the main characteristics that affect the wing twist angle and lift efficiency. The Jig shape can be frozen with the increasing stiffness ratio less than 1.1. And linear relationship between elastic aerodynamic derivatives and stiffness ratio is established.