Abstract: A supporting structure for a chair, the supporting structure is a seat, a back support or a headrest. A nylon mesh is fixed on the annular upper surface of an inwardly projecting flange of the frame, and then the plastic-injection-molded engaging layer is integrally formed on the exterior surface of the frame, enabling the mesh to be firmly fixed on the frame. The elasticity of the mesh provides a comfortable and adequate support for the user's buttocks, back and head, providing comfortable seating and preventing muscle soreness. Further, the heat caused by the user's body can be vented off via the apertures of the mesh, so that the user will feel cool when sitting on or leaning against the supporting structure.