Abstract: A method for the production of low enriched uranium hexafluoride from highly enriched metallic uranium consists of oxidizing metallic uranium highly enriched in uranium-235 at a temperature of 700.degree.-1100.degree. C. and fluorinating with elementary fluorine at temperature of 300.degree.-1500.degree. C. with a fluorine excess exceeding the stoichiometric value, then sublimating and mixing in a gas flow the resultant highly enriched uranium hexafluoride with uranium hexafluoride containing uranium-235 within a range from 0.2 to 4.9% by weight, in a ratio defined by the equation: ##EQU1## where C.sup.HEU is the content of uranium-235 in the highly enriched uranium,C.sup.LEU is the content of uranium-235 in the low enriched uranium,C is the content of uranium-235 in uranium, the hexafluoride of which is used for mixing.