Strubl's polarographic method for the determination of uranium in the presence of iron can be used for the determination of uranium in plutonium solutions. A hydroxylamine hydrochloride solution (2M) is used as the supporting electrolyte. This reduces the plutonium to the plus three oxidation state without reducing the uranium. The uranium may then be determined polarographically by measuring the height of the uranyl reduction wave (UVI to UV) at -0.35 volts (vs. S.C.E.) applied potential. Solutions with a U/Pu weight ratio as low as 3.5 x 10(-3) were analyzed with an error of less than 2%. This error increased to 6% for solutions of 1 x 10(-3) U/Pu ration and is considerably larger for smaller U/Pu ratios.