High-resolution 19F MAS NMR spectra of polytetrafluorotheylene (PTFE) oligomers in the solid state were measured. On the basis of the obtained spectra, their structural analyses were successfully made. It was found that PTFE oligomers obtained by reaction of high molecular weight PTFE with fluorine gas at high temperature have CF 3 groups and branched groups. Further, it was found that the existence of these groups in PTFE oligomers significantly affects the surface energy of the polymer, which leads to a variety of properties.