Rare earth solution (RES) surface modification and acid treatment methods were used to functionalize carbon nanotubes (CNTs). CNT composite thin films were prepared on hydroxylated glass substrates by a self-assembling process from specially formulated solution. Atomic force microscopy, x-ray photoelectron spectrometry, and scanning electron microscopy were used to characterize the thin films. Tribological properties of the CNT thin films sliding against a steel ball were evaluated on a friction and wear tester. The experimental results showed that the friction coefficient of the glass substrate was reduced from 0.85 to 0.1 after the formation of CNT composite self-assembled film on its surface, and the film exhibited good wear resistant property. The superior friction reduction and wear resistance of CNT composite films were attributed to the improvement of load-bearing capacity afforded by the chemical bond between CNTs and the films as well as good adhesion of the films to the substrate.