Polyimide composites are extensively utilized in aircraft and engine structural design due to their superior high-temperature resistance properties. An aircraft polyimide composite exhaust nozzle structure is designed and fabricated based on the material characteristics and performance properties of polyimide composite. Furthermore, the factors impacting the application of polyimide composite in exhaust nozzles are examined through topological optimization and thermomechanical coupling strength analysis as well as integrated manufacturing optimization technologies. Consequently, typical design and application methodologies for polyimide composites have been established, which is verified and validated by the high precision manufacturing of typical 2-meter typical barrel structure and its static strength test. The results demonstrate that the exhaust nozzle designed and manufactured using HST300/CCF800 polyimide composite material can withstand 100% of the design load, and the stress and strain distributions are consistent with the design expectations.