This paper studesan optimal design technique of composite honeycomb sandwich inlet structure based on the global response surface algorithm. Taking composite honeycomb sandwich inlet structure as the research object, the technique aims to the lightest weight of structure. Based on the production process of actual engineering and the general principles of composite structure design, the discrete variables are selected for the layer thickness of different ply direction angles and the thickness of honeycomb core. Various failure modes of composite honeycomb sandwich structure as well as the frequency requirements of the inlet working environment are constrained. Finally, a numerical example verifies the feasibility of the proposed method.