Abstract: It is suggested to use 0.5 mol/l HClO_4-0.5 mol/l NaNO_3-0.1mol/l NaClO_4as supporting electrolyte for determinating ruthenium. In the supproting electrolytethere is a clear polarographic wave of ruthenium (IV) at -0.8V vs. SCE. Thewave height of ruthenium(IV) is linear in the range from 0.1 to 4.0μg.ml~(-1). The effect of the component of supporting electrolyte and the other ion inthe samples on the measurement of ruthenium are studied. The analysis methodsfor measuring ruthenium in both acidic or basic imitative radioactive wastesolutions which is used in study of glass solidification are worked out. Imitativesamples are analysised.