<p>The WC/a-C nano-multilayer film and nanocomposite film were fabricated using a non-equilibrium magnetron sputtering system. The tribological behavior of these two types of films was systematically investigated within the load range of 1–9 N. The results indicated that the nanocomposite film exhibits superior tribological properties compared to the nano-multilayer film. Under identical loading conditions, the friction coefficient of the nanocomposite film was lower, particularly achieving a value as low as 0.07 under a 7 N load. This is mainly because that the β-WC_1-x phase at the interface of the nanocomposite film is easily oxidized to form WO₃ under the friction-induced action, and the sliding interface gradually changed from the C/C interface to the WO₃/C interface with weak intrinsic adhesion for the nanocomposite film under higher loads of 5–9 N. Additionally, the wear rate of both films increased with increasing load; however, the nanocomposite film demonstrated excellent wear resistance owing to its favorable microstructure and strength-toughness. Notably, under a high load of 9 N, the wear rate of the nanocomposite film was approximately 1.77 × 10^-6 mm³/Nm, representing a reduction of 7.81% compared to that of the nano-multilayer film. These findings suggest that the nanocomposite film is better suited for high-load friction and wear applications. This study provides an experimental basis for the application of these two films in harsh environments.</p> Graphical Abstracts <p></p>