Intrinsic point defect formation in a fluorine-doped synthetic silica (SiO2) glass by (CO)-C-60 gamma-ray irradiation was examined. The most abundantly formed defects are oxygen vacancies (Si-Si bonds). The concentrations of Si-Si bonds and interstitial oxygen molecules increase almost linearly with the gamma-ray dose. These observations indicate that the primarily intrinsic defect process in SiO2 glass irradiated with (CO)-C-60 gamma-rays is the Frenkel pair formation, rather than a simple cleavage of an Si-O bond into a pair of silicon and oxygen dangling bonds.