For aeroelastic problems of civil aircraft， optimization design at the conceptual design stage is carried out to avoid subsequent design alteration or even redesign. Taking a high aspect ratio wing as an example， structural stiffness distribution is preliminarily determined by referring to similar aircrafts， and structural weight is minimized as the optimization objective. Adopting limit flutter speed， maximum deformation of wing tip， maximum stress of wing root and divergence speed as the constraint conditions， aeroelasticity problem of the wing is solved by using the optimization iteration method. Results demonstrate that under the given constraints， flutter speed of the wing meets the flutter stability requirement， and the strength， stiffness and static divergence characteristics also meet the design requirements. And according to the optimization results， stiffness distribution indexes along the wing span are obtained， which provides guidance for the structural layout of civil aircraft at the conceptual design stage.