In the present work, two polyetheretherketone (PEEK) composites, i.e. conventional composite filled with short carbon fibers (SCF) and nanocomposite filled with SiO₂ nanoparticles, were mechanically assembled side-by-side using adhesive. The tribological behavior of the assembled sample was investigated using a Pin-On-Disc tribometer with the two composites' surfaces rubbing in succession along the same wear track on a steel counterpart. It was demonstrated that the assembled sample exhibited a greatly enhanced tribological performance in comparison to those obtained when the composites ran respectively. A synergetic role of the conventional composite and the nanocomposite was therefore identified. Moreover, it was manifested that the assembled sample showed a tribological performance comparable to the hybrid nanocomposite filled with combined SCF and SiO₂ nanoparticles. The tribological mechanisms dominating the synergetic effect of the two composites were analyzed based on direct comparisons of tribofilm morphologies. It is expected that the present work provides a new design concept for tribo-enginnering components, i.e. assembling individual composites with specific functionalities.