**Abstract**

In recent years, a scientific shift has been observed that the use of carbon-based nanomaterials in different composite materials can improve their mechanical, thermal, and electrical properties. Different carbon-based nanomaterials have various structures and mechanical, electrical, and thermal conductivity characteristics. By combining with different material composite methods, carbon composite materials with different structures can be prepared. Through the optimization of material structure, carbon composite materials with high performance can be obtained. SP2 hybrid carbon materials, such as carbon nanotubes (CNTs), carbon fiber (CF), and graphene, have excellent electrical, thermal, and mechanical properties due to their regular carbon sixmembered ring structure, so they are the main low-dimensional carbon materials and are widely used in composite research. In this chapter, the research progress of carbon nanotubes, carbon fibers, and graphene-based fibers (GBFs) in composite materials are introduced, respectively, and the preparation method, molding process, performance, and application in industry are summarized. Finally, the existing problems and future development trend of carbon-based composites are prospected.

**Keywords:** carbon-based nanomaterials, carbon nanotubes (CNTs), carbon fibers (CF), graphene-based fibers (GBFs), fiber composites
