Since the discovery of carbon nanotubes (CNTs), the remarkable mechanical properties such as high tensile strength, high flexibility, high heat conductance have attracted many interests. And the synthesis of high quality CNTs using various methods have studied. Kusunoki et al. have reported that CNTs with high-density and well-alignment are formed vertically on a silicon carbide substrate. CNTs on SiC substrate could be used for tribomaterial with high adherence because each CNT covalently bonds with the SiC substrate. Thus, we have studied about interfacial strength of CNT films made by surface decomposition of SiC by using atomic force microscopy. And considering the non linear bending theory on bending (or moment at the interface of CNT films), the wear mechanism was discussed.