In view of the characteristics of weak rigidity and easy deformation of parts during aircraft assembly process, an optimization method based on genetic algorithm for the clamping scheme of the weak rigid thin-walled parts of the aircraft is proposed. The objective of this method is to minimize the maximum deformation of thin-walled components caused by gravity external loads. A synchronous optimization model of clamping layout and clamping sequence is established. The maximum deformation of the thin-walled components under the clamping scheme is obtained through finite element simulation, and the optimization model is solved by genetic algorithm and finite element batch technology. Finally, taking the typical aircraft part long truss as an example, the feasibility and effectiveness of the method are verified.