With the continuous improvement of living standards, the application and demand for fiber thermal insulation materials are growing. The development of porous fiber- based thermal insulation composites with hollow structure is of great significance. In view of the current structural characteristics of braid-reinforced hollow fiber membranes, including high porosity polymer separation layer, three-dimensional network fiber braided tube, and large cavities, this study combined dry/wet spinning technology with hot pressing molding process. Firstly, the braid-reinforced polyurethane (PU) hollow fiber membrane with incomplete phase separation was prepared by dry/wet spinning technology. It was then accumulated and formed into a multi-layer fiber composite structure on the winding wheel. Finally, the fiber membrane was further bonded and molded through hot pressing process, successfully preparing composites based on braid- reinforced PU hollow fiber membranes. The influence of hot pressing temperature on the structure and properties of the composites was investigated. The results show that the hollow fiber membranes in the prepared composite are arranged in parallel diagonal configuration, with good fiber bonding and each three fibers in contact forming an irregular cavity. The hot pressing temperature has an impact on the thickness, fracture stress, elongation at break, and air permeability of the composites. When the hot pressing temperature is 120 ℃, the thermal insulation rate of the composite reaches 41.70%, providing a new approach for the preparation of thermal insulation materials. In addition, the average sound absorption coefficient of the composite reaches 0.37, indicating potential applications in the field of sound absorption and noise reduction in the future.