Proton radiation responses of Si gate P and N channel fluorinated MOSFETs processed with H2+ O2 and dry O2 gate oxidation have been investigated. The data on threshold voltage and Ids-Vgs characteristics show that the radiation-induced oxide charges and interface stales can be restrained. The formation of Si-F bonds to substitute some weak bonds and strained bonds which easily become charge traps under irradiation and the relaxation of the Si/SiO2 interface stress by F atoms are considered to explain the experimental result.