Poly(ethylene glycol)-carbon nanotubes (PEG-CNTs) were successfully prepared. Results of four-ball tribotester indicated that both the load-carrying capacity and anti-wear of the PEG-CNTs were superior to those PEG owing to the additive reinforced by CNTs. The nanocomposite thin films have been fabricated on mica by spin casting technique. AFM investigations provide insights into the roughness and microtribological properties on a micro scale. The polymer in the film is the guarantee of flat surface, and the rigid CNTs enhance load-bearing property of the thin film.