A surface derivatization technique was applied to the XPS analysis of inorganic carbons. Radiofrequency (13. 56 MHz) plasma with CF₄ gas has been used for the surface derivatization. Various kinds of graphites and diamonds that had been analysed by XRD and EELS were studied. The XPS data were analyzed with regard to the difference of binding energy between C_1s-F_1s (ΔE_F-C), and the ratio of fluorine and carbon (F/C). It was found that diamond, graphite and amorphous-carbon could be discriminated with ΔE_F-C, and that crystallinity could be estimated with F/C.