[en] A method for the determination of uranium content in enriched U-Al alloys is described. The mass-spectrometric isotope dilution method was proposed and verified for the determination of uranium in these materials. A solution of natural uranyl-nitrate, prepared by dissolution of standard reference material NBS-U-960, was used as a spike. Uranium was spearated from aluminium in the form of chloro complexes by sorption on anion exchange resin Dowex 1 -X8 from 9M HCl. The error of determination lies in an interval 0.03-0.07% rel. for uranium contents 18.2-22 8 wt%. (author)