The diameters of future heavy launch vehicles for manned lunar landing and deep space exploration are 1-2 times larger than those of the currently used Chinese rockets. To meet the requirement of high-stiffness, lightweight and high reliability by Extra-large resin matrix composites structures, the performance of future materials and processing level of large scale structures must be improved greatly than the existing system. The project of research on the engineering application of critical material system in structural composite material proposed by CASC The diameters of future heavy launch vehicles for manned lunar landing and deep space exploration are 1-2 times larger than those of the currently used Chinese rockets. To meet the requirement of high-stiffness, lightweight and high reliability by Extra-large resin matrix composites structures, the performance of future materials and processing level of large scale structures must be improved greatly than the existing system. The project of research on the engineering application of critical material system in structural composite material proposed by CASC