Landing gear system plays an important role in the process of takeoff and landing, and it’s a critical part to ensure flight operation safety, thus the landing gear design occupies a crucial position in aircraft design process. The conceptual design of landing gear is the first step of whole design process, which largely determines the final design results. The application of QFD (Quality Function Deployment) method in landing gear system can build a conversion model from landing gear system requirements to technical characteristics, parts and manufacturing process. While the application of rough number can make the conversion of requirements more objective and accurate. Compared with detailed design, the conceptual design method of QFD can realize overall planning and multi-dimensional optimization. In the later design stage, according to different design requirements or parameter constraints, the optimization scheme can be obtained faster by referring to the QFD model.