We have previously reported that low-degradation XPS depth profiling of a polymer was effectively observed using C₆₀ ion beam sputtering. However, the suitable sputtering condition for C₆₀ ion beam has not been studied in detail yet. In this paper, we would like to discuss the influence of C₆₀ ion beam angle of incidence upon XPS depth profiling for organic polymers. The results obtained are: (1) Relative sputtering yield for SiO₂ was increased with the angle of incidence, (2) Carbon residue in the sputtered Si substrate is decreased with the higher angle of incidence (3) Degradation of atomic concentration (C and O concentration) and chemical states for both carbon and oxygen in polyethylene-terephthalate remained relatively intact by using a grazing angle of 75 degree. In conclusion, the higher angle of incidence seems to be better for the XPS depth profiling using C₆₀ ion beam.