Products from the irradiation of ten pure perfluoroalkanes at 25°C by 50 to 150 Mrads of γ-rays have been analyzed by gas-liquid chromatography. The numbers of molecules that disappeared per 100 eV absorbed were found to be: ${\rm CF}_{4}(1.1),\ {\rm C}_{2}{\rm F}_{6}(4.0),\ {\rm C}_{3}{\rm F}_{8}(3.7),\ n\text{-}{\rm C}_{4}{\rm F}_{10}(3.7),\ i\text{-}{\rm C}_{4}{\rm F}_{10}(3.3),\ n\text{-}{\rm C}_{5}{\rm F}_{12}(3.1),\ n\text{-}{\rm C}_{6}{\rm F}_{14}(2.9),\ 2\text{-}{\rm CF}_{3}{\rm C}_{5}{\rm F}_{11}(2.7),\ 3\text{-}{\rm CF}_{3}{\rm C}_{5}{\rm F}_{11},(2.6)$ and $2,3\text{-}({\rm CF}_{3})_{2}\text{-}{\rm C}_{4}{\rm F}_{8}(5.0)$ . The preponderance of branched product molecules containing CF3 groups indicates that C-F bonds at secondary and tertiary carbon are more susceptible to radiation damage than those at CF3 groups.