Abstract: Robust optimization design of aeroelastic st ructures was investigated by using the genetic-gradient hybrid algorithm. The method was applied to an optimization design process of a robust aeroelastic structure with the high-aspect-ratio composite wing, which demonst rates the applicability and the efficiency of the method. The difference was revealed by comparing a robust structural optimal design with a traditional optimal design. The research indicates that a structure resulting from an optimization, in which the robustness constrains are taken into accoun , is more anti-jamming than a structure resulting from a traditional way, when the design variables are uncertain. However, the mass increment is paid for satisfying the robustness requirement. The higher robustness the structure needs, the greater the mass increment is.