Amberlite XAD-2 resin was impregnated with Cyanex272 {bis (2,4,4-trimethylpentyl) phosphinic acid} and Cyanex302 {bis (2,4,4-trimethylpentyl) monothiophosphinic acid}. Systematic studies of Cyanex302 impregnated XAD-2 were carried out to develop optimum conditions for uranium(VI) sorption and devise its separation from rare earth elements. Amberlite XAD-2 impregnated with Cyanex302 had poor distribution coefficients for lanthanum(III) and neodymium(III) while uranium(VI) was quantitatively sorbed from 1 x 10(-3) M HNO3 and was recovered with 1 M HCl from the solid phase. The method proposed is simple, selective and reproducible for determination of uranium(VI) with a relative standard deviation (RSD) of 0.4 %.