In view of the development demand and challenge for the naval ship technology, this paper briefly analyzes the necessity and urgency of developing the application engineering of composite structures, from the perspective of the overall ship performance, integrated stealthiness, and integrated logistics support. Taking the application of submarines in western navies as examples, this paper summarizes the development approaches of the application of composite structures in naval ships, and puts forward and expounds upon three "integrated" technical features of the application engineering of functional composite structures. Moreover, a discussion is included to emphasize the definitions concerning overall and structural design technology of naval ships, as well as their connotation and composition of key technology. This paper concludes with the recommendation that the top-level design should be constructed as soon as possible, in the meantime, enhancing the capability of basic design research and establishment of standardization systems in response to the future development requirements demanded of Chinese naval ships in this field.