The thermoplastic composite is a promising candidate for automobile and aerospace industries as a high-performance material having desired light-weight. Also the thermoplastic composite can be welded or recycled upon melting, and be manufactured faster than the thermoset one. In despite of the advantages of the thermoplastic composite, it is hard to manufacture using original resin transfer molding (RTM) process, because of the high viscosity of polymer melts. So reactive processing has been suggested for the thermoplastic composite, where the low viscosity monomer melts instead of polymer melts are injected between fibers, and following in-situ polymerization enables to produce the thermoplastic composite. Recently we optimized the reactive processing system for carbon fiber-reinforced polyamide-6 composite. In the system, the anionic ring-opening polymerization of å-caprolactam was utilized with a proper catalyst for polyamide-6 matrix. The produced carbon fiber-reinforced polyamide-6 (PA-6) composite was discussed in terms of mechanical properties. Furthermore, high-speed resin transfer molding (RTM), strong interfacial interaction formation between polyamide-6 (PA-6) matrix and carbon fiber, and high-performance comparable with thermoset one will be investigated.